A person who is directly or indirectly involved in the provisioning of healthcare.

A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content. Often, this is a reference to an implementation guide that defines the special rules along with other profiles etc.

Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element. Often, when used, the URL is a reference to an implementation guide that defines these special rules as part of it's narrative along with other profiles, value sets, etc.

May be used to represent additional information that is not part of the basic definition of the resource and that modifies the understanding of the element that contains it and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

An identifier that applies to this person in this role.

NPI must be supported as the identifier system in the US, Tax id is allowed, Local id is allowed in addition to another identifier supplied by a jurisdictional authority such as a practitioner's Drug Enforcement Administration (DEA) number.

Often, specific identities are assigned for the agent.

The purpose of this identifier.

Applications can assume that an identifier is permanent unless it explicitly says that it is temporary.

Identifies the purpose for this identifier, if known .

Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers.

A coded type for the identifier that can be used to determine which identifier to use for a specific purpose.

This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type.

A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.

Allows users to make use of identifiers when the identifier system is not known.

Establishes the namespace for the value - that is, a URL that describes a set values that are unique.

Identifier.system is always case sensitive.

There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers.

The portion of the identifier typically relevant to the user and which is unique within the context of the system.

If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe.

An identifier that applies to this person in this role.

Often, specific identities are assigned for the agent.

Whether this practitioner's record is in active use.

If the practitioner is not in use by one organization, then it should mark the period on the PractitonerRole with an end date (even if they are active) as they may be active in another role.

Need to be able to mark a practitioner record as not to be used because it was created in error.

The name(s) associated with the practitioner.

The selection of the use property should ensure that there is a single usual name specified, and others use the nickname (alias), old, or other values as appropriate.

In general, select the value to be used in the ResourceReference.display based on this:

1. There is more than 1 name
2. Use = usual
3. Period is current to the date of the usage
4. Use = official
5. Other order as decided by internal business rules.

The name(s) that a Practitioner is known by. Where there are multiple, the name that the practitioner is usually known as should be used in the display.

Identifies the purpose for this name.

Applications can assume that a name is current unless it explicitly says that it is temporary or old.

The use of a human name.

Allows the appropriate name for a particular context of use to be selected from among a set of names.

Specifies the entire name as it should be displayed e.g. on an application UI. This may be provided instead of or as well as the specific parts.

Can provide both a text representation and parts. Applications updating a name SHALL ensure that when both text and parts are present, no content is included in the text that isn't found in a part.

A renderable, unencoded form.

The part of a name that links to the genealogy. In some cultures (e.g. Eritrea) the family name of a son is the first name of his father.

Family Name may be decomposed into specific parts using extensions (de, nl, es related cultures).

Given name.

If only initials are recorded, they may be used in place of the full name parts. Initials may be separated into multiple given names but often aren't due to paractical limitations. This element is not called "first name" since given names do not always come first.

A contact detail for the practitioner, e.g. a telephone number or an email address.

Person may have multiple ways to be contacted with different uses or applicable periods. May need to have options for contacting the person urgently and to help with identification. These typically will have home numbers, or mobile numbers that are not role specific.

Need to know how to reach a practitioner independent to any roles the practitioner may have.

An extension representing the days and times a contact point is available

A reference to an alternative point of contact (plannet-PractitionerRole, plannet-Organization, plannet-OrganizationAffiliation, or plannet-Location) for this organization

Telecommunications form for contact point - what communications system is required to make use of the contact.

Telecommunications form for contact point.

The actual contact point details, in a form that is meaningful to the designated communication system (i.e. phone number or email address).

Additional text data such as phone extension numbers, or notes about use of the contact are sometimes included in the value.

Need to support legacy numbers that are not in a tightly controlled format.

Identifies the purpose for the contact point.

Applications can assume that a contact is current unless it explicitly says that it is temporary or old.

Use of contact point.

Need to track the way a person uses this contact, so a user can choose which is appropriate for their purpose.

Address(es) of the practitioner

The PractitionerRole does not have an address value on it, as it is expected that the location property be used for this purpose (which has an address).

-

The absolute geographic location of the Location, expressed using the WGS84 datum (This is the same co-ordinate system used in KML).

The extension can be further extended to include unique geolocation identifiers, confidence, altitude, etc.

The purpose of this address.

Applications can assume that an address is current unless it explicitly says that it is temporary or old.

The use of an address.

Allows an appropriate address to be chosen from a list of many.

This component contains the house number, apartment number, street name, street direction, P.O. Box number, delivery hints, and similar address information.

The name of the city, town, suburb, village or other community or delivery center.

Sub-unit of a country with limited sovereignty in a federally organized country. A code may be used if codes are in common use (e.g. US 2 letter state codes).

Two letter USPS alphabetic codes.

A postal code designating a region defined by the postal service.

Country - a nation as commonly understood or generally accepted.

ISO 3166 3 letter codes can be used in place of a human readable country name.

The official certifications, training, and licenses that authorize or otherwise pertain to the provision of care by the practitioner. For example, a medical license issued by a medical board authorizing the practitioner to practice medicine within a certian locality.

An Extension

An extension to add status and whereValid elements to a practitioner’s qualifications.

May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

An identifier that applies to this person's qualification in this role.

Often, specific identities are assigned for the qualification.

Coded representation of the qualification.

Period during which the qualification is valid.

Qualifications are often for a limited period of time, and can be revoked.

Organization that regulates and issues the qualification.

A language the practitioner can use in patient communication.

The structure aa-BB with this exact casing is one the most widely used notations for locale. However not all systems code this but instead have it as free text. Hence CodeableConcept instead of code as the data type.

A human language.

Knowing which language a practitioner speaks can help in facilitating communication with patients.

An extension to express a practitioner’s spoken proficiency with the language indicated in practitioner.communication.

A person who is directly or indirectly involved in the provisioning of healthcare.

The logical id of the resource, as used in the URL for the resource. Once assigned, this value never changes.

The only time that a resource does not have an id is when it is being submitted to the server using a create operation.

The metadata about the resource. This is content that is maintained by the infrastructure. Changes to the content might not always be associated with version changes to the resource.

A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content. Often, this is a reference to an implementation guide that defines the special rules along with other profiles etc.

Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element. Often, when used, the URL is a reference to an implementation guide that defines these special rules as part of it's narrative along with other profiles, value sets, etc.

The base language in which the resource is written.

Language is provided to support indexing and accessibility (typically, services such as text to speech use the language tag). The html language tag in the narrative applies to the narrative. The language tag on the resource may be used to specify the language of other presentations generated from the data in the resource. Not all the content has to be in the base language. The Resource.language should not be assumed to apply to the narrative automatically. If a language is specified, it should it also be specified on the div element in the html (see rules in HTML5 for information about the relationship between xml:lang and the html lang attribute).

A human language.

A human-readable narrative that contains a summary of the resource and can be used to represent the content of the resource to a human. The narrative need not encode all the structured data, but is required to contain sufficient detail to make it "clinically safe" for a human to just read the narrative. Resource definitions may define what content should be represented in the narrative to ensure clinical safety.

Contained resources do not have narrative. Resources that are not contained SHOULD have a narrative. In some cases, a resource may only have text with little or no additional discrete data (as long as all minOccurs=1 elements are satisfied). This may be necessary for data from legacy systems where information is captured as a "text blob" or where text is additionally entered raw or narrated and encoded information is added later.

These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, and nor can they have their own independent transaction scope.

This should never be done when the content can be identified properly, as once identification is lost, it is extremely difficult (and context dependent) to restore it again. Contained resources may have profiles and tags In their meta elements, but SHALL NOT have security labels.

May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

May be used to represent additional information that is not part of the basic definition of the resource and that modifies the understanding of the element that contains it and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

An identifier that applies to this person in this role.

NPI must be supported as the identifier system in the US, Tax id is allowed, Local id is allowed in addition to another identifier supplied by a jurisdictional authority such as a practitioner's Drug Enforcement Administration (DEA) number.

Often, specific identities are assigned for the agent.

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

The purpose of this identifier.

Applications can assume that an identifier is permanent unless it explicitly says that it is temporary.

Identifies the purpose for this identifier, if known .

Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers.

A coded type for the identifier that can be used to determine which identifier to use for a specific purpose.

This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type.

A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.

Allows users to make use of identifiers when the identifier system is not known.

Establishes the namespace for the value - that is, a URL that describes a set values that are unique.

Identifier.system is always case sensitive.

There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers.

The portion of the identifier typically relevant to the user and which is unique within the context of the system.

If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe.

Time period during which identifier is/was valid for use.

Organization that issued/manages the identifier.

The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization.

An identifier that applies to this person in this role.

Often, specific identities are assigned for the agent.

Whether this practitioner's record is in active use.

If the practitioner is not in use by one organization, then it should mark the period on the PractitonerRole with an end date (even if they are active) as they may be active in another role.

Need to be able to mark a practitioner record as not to be used because it was created in error.

The name(s) associated with the practitioner.

The selection of the use property should ensure that there is a single usual name specified, and others use the nickname (alias), old, or other values as appropriate.

In general, select the value to be used in the ResourceReference.display based on this:

1. There is more than 1 name
2. Use = usual
3. Period is current to the date of the usage
4. Use = official
5. Other order as decided by internal business rules.

The name(s) that a Practitioner is known by. Where there are multiple, the name that the practitioner is usually known as should be used in the display.

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

Identifies the purpose for this name.

Applications can assume that a name is current unless it explicitly says that it is temporary or old.

The use of a human name.

Allows the appropriate name for a particular context of use to be selected from among a set of names.

Specifies the entire name as it should be displayed e.g. on an application UI. This may be provided instead of or as well as the specific parts.

Can provide both a text representation and parts. Applications updating a name SHALL ensure that when both text and parts are present, no content is included in the text that isn't found in a part.

A renderable, unencoded form.

The part of a name that links to the genealogy. In some cultures (e.g. Eritrea) the family name of a son is the first name of his father.

Family Name may be decomposed into specific parts using extensions (de, nl, es related cultures).

Given name.

If only initials are recorded, they may be used in place of the full name parts. Initials may be separated into multiple given names but often aren't due to paractical limitations. This element is not called "first name" since given names do not always come first.

Part of the name that is acquired as a title due to academic, legal, employment or nobility status, etc. and that appears at the start of the name.

Part of the name that is acquired as a title due to academic, legal, employment or nobility status, etc. and that appears at the end of the name.

Indicates the period of time when this name was valid for the named person.

Allows names to be placed in historical context.

A contact detail for the practitioner, e.g. a telephone number or an email address.

Person may have multiple ways to be contacted with different uses or applicable periods. May need to have options for contacting the person urgently and to help with identification. These typically will have home numbers, or mobile numbers that are not role specific.

Need to know how to reach a practitioner independent to any roles the practitioner may have.

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

An extension representing the days and times a contact point is available

A reference to an alternative point of contact (plannet-PractitionerRole, plannet-Organization, plannet-OrganizationAffiliation, or plannet-Location) for this organization

Telecommunications form for contact point - what communications system is required to make use of the contact.

Telecommunications form for contact point.

The actual contact point details, in a form that is meaningful to the designated communication system (i.e. phone number or email address).

Additional text data such as phone extension numbers, or notes about use of the contact are sometimes included in the value.

Need to support legacy numbers that are not in a tightly controlled format.

Identifies the purpose for the contact point.

Applications can assume that a contact is current unless it explicitly says that it is temporary or old.

Use of contact point.

Need to track the way a person uses this contact, so a user can choose which is appropriate for their purpose.

Specifies a preferred order in which to use a set of contacts. ContactPoints with lower rank values are more preferred than those with higher rank values.

Note that rank does not necessarily follow the order in which the contacts are represented in the instance.

Time period when the contact point was/is in use.

Address(es) of the practitioner

The PractitionerRole does not have an address value on it, as it is expected that the location property be used for this purpose (which has an address).

-

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

The absolute geographic location of the Location, expressed using the WGS84 datum (This is the same co-ordinate system used in KML).

The extension can be further extended to include unique geolocation identifiers, confidence, altitude, etc.

The purpose of this address.

Applications can assume that an address is current unless it explicitly says that it is temporary or old.

The use of an address.

Allows an appropriate address to be chosen from a list of many.

Distinguishes between physical addresses (those you can visit) and mailing addresses (e.g. PO Boxes and care-of addresses). Most addresses are both.

The definition of Address states that "address is intended to describe postal addresses, not physical locations". However, many applications track whether an address has a dual purpose of being a location that can be visited as well as being a valid delivery destination, and Postal addresses are often used as proxies for physical locations (also see the Location resource).

The type of an address (physical / postal).

Specifies the entire address as it should be displayed e.g. on a postal label. This may be provided instead of or as well as the specific parts.

Can provide both a text representation and parts. Applications updating an address SHALL ensure that when both text and parts are present, no content is included in the text that isn't found in a part.

A renderable, unencoded form.

This component contains the house number, apartment number, street name, street direction, P.O. Box number, delivery hints, and similar address information.

The name of the city, town, suburb, village or other community or delivery center.

The name of the administrative area (county).

District is sometimes known as county, but in some regions 'county' is used in place of city (municipality), so county name should be conveyed in city instead.

Sub-unit of a country with limited sovereignty in a federally organized country. A code may be used if codes are in common use (e.g. US 2 letter state codes).

Two letter USPS alphabetic codes.

A postal code designating a region defined by the postal service.

Country - a nation as commonly understood or generally accepted.

ISO 3166 3 letter codes can be used in place of a human readable country name.

Time period when address was/is in use.

Allows addresses to be placed in historical context.

Administrative Gender - the gender that the person is considered to have for administration and record keeping purposes.

The gender of a person used for administrative purposes.

Needed to address the person correctly.

The date of birth for the practitioner.

Needed for identification.

Image of the person.

Many EHR systems have the capability to capture an image of patients and personnel. Fits with newer social media usage too.

The official certifications, training, and licenses that authorize or otherwise pertain to the provision of care by the practitioner. For example, a medical license issued by a medical board authorizing the practitioner to practice medicine within a certian locality.

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

An Extension

An extension to add status and whereValid elements to a practitioner’s qualifications.

May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

An identifier that applies to this person's qualification in this role.

Often, specific identities are assigned for the qualification.

Coded representation of the qualification.

Period during which the qualification is valid.

Qualifications are often for a limited period of time, and can be revoked.

Organization that regulates and issues the qualification.

A language the practitioner can use in patient communication.

The structure aa-BB with this exact casing is one the most widely used notations for locale. However not all systems code this but instead have it as free text. Hence CodeableConcept instead of code as the data type.

A human language.

Knowing which language a practitioner speaks can help in facilitating communication with patients.

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

An extension to express a practitioner’s spoken proficiency with the language indicated in practitioner.communication.

A reference to a code defined by a terminology system.

Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true.

Allows for alternative encodings within a code system, and translations to other code systems.

A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user.

Very often the text is the same as a displayName of one of the codings.

The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source.