Last-Modified (HTTP header)
E736181
Last-Modified is an HTTP response header that indicates the date and time at which the origin server believes the requested resource was last changed, enabling caching and conditional requests.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Last-Modified (HTTP header) canonical | 2 |
How this entity was disambiguated
This entity first appeared as the object of triple T8486757 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Last-Modified (HTTP header) Context triple: [Date (HTTP header), relatedTo, Last-Modified (HTTP header)]
-
A.
If-None-Match
If-None-Match is an HTTP request header used for conditional requests, typically with ETags, to perform cache validation or conditional updates without unnecessarily transferring data.
-
B.
RFC 7232
RFC 7232 is an HTTP/1.1 specification that defines conditional request mechanisms using validators like ETags and Last-Modified to support efficient caching and concurrency control on the web.
-
C.
RFC 7235
RFC 7235 is an IETF specification that defined the HTTP/1.1 authentication framework, including the use of challenge-response mechanisms like Basic and Digest authentication.
-
D.
RFC 7234
RFC 7234 is an IETF specification that defines HTTP/1.1 caching semantics, including how responses may be stored, reused, and validated by caches.
-
E.
RFC 7231
RFC 7231 is an IETF specification that defined the semantics and content of the HTTP/1.1 protocol, including methods, status codes, and header fields, before being superseded by RFC 9112.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Last-Modified (HTTP header) Target entity description: Last-Modified is an HTTP response header that indicates the date and time at which the origin server believes the requested resource was last changed, enabling caching and conditional requests.
-
A.
If-None-Match
If-None-Match is an HTTP request header used for conditional requests, typically with ETags, to perform cache validation or conditional updates without unnecessarily transferring data.
-
B.
RFC 7232
RFC 7232 is an HTTP/1.1 specification that defines conditional request mechanisms using validators like ETags and Last-Modified to support efficient caching and concurrency control on the web.
-
C.
RFC 7235
RFC 7235 is an IETF specification that defined the HTTP/1.1 authentication framework, including the use of challenge-response mechanisms like Basic and Digest authentication.
-
D.
RFC 7234
RFC 7234 is an IETF specification that defines HTTP/1.1 caching semantics, including how responses may be stored, reused, and validated by caches.
-
E.
RFC 7231
RFC 7231 is an IETF specification that defined the semantics and content of the HTTP/1.1 protocol, including methods, status codes, and header fields, before being superseded by RFC 9112.
- F. None of above. chosen
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf | HTTP response header field ⓘ |
| actsAs | weak validator ⓘ |
| appliesTo |
resource state
ⓘ
selected representation ⓘ |
| canBe | strong validator ⓘ |
| canBeOmittedWhen |
resource is known to change frequently
ⓘ
server cannot determine modification time ⓘ |
| category | response header ⓘ |
| comparisonGranularity | one-second resolution ⓘ |
| definedIn |
RFC 7232
ⓘ
RFC 9110 ⓘ |
| enables |
304 Not Modified responses
ⓘ
conditional GET ⓘ conditional HEAD ⓘ |
| exampleValue | Last-Modified: Wed, 21 Oct 2015 07:28:00 GMT ⓘ |
| format | HTTP-date ⓘ |
| hasFieldName | Last-Modified ⓘ |
| headerSection | response header section ⓘ |
| indicates | date and time the origin server believes the selected representation was last modified ⓘ |
| influences |
cache freshness validation
ⓘ
revalidation policy ⓘ |
| interactsWith |
Cache-Control
ⓘ
Expires ⓘ |
| mayDifferFrom | actual last modification time on origin server ⓘ |
| mustNotBeInFuture | relative to server time ⓘ |
| notAllowedIn | HTTP request headers ⓘ |
| partOf |
Hypertext Transfer Protocol
ⓘ
linked to:
HTTP
|
| relatedTo |
ETag
ⓘ
If-Modified-Since ⓘ If-Unmodified-Since ⓘ Last-Modified validator ⓘ |
| replacedSpecification | RFC 2616 ⓘ |
| securityConsideration | can reveal information about resource change history ⓘ |
| semantics | representation metadata ⓘ |
| setBy | origin server ⓘ |
| status | standard HTTP header ⓘ |
| timeZoneRequirement | GMT ⓘ |
| usedBy |
caches
ⓘ
intermediaries ⓘ user agents ⓘ |
| usedFor |
HTTP caching
ⓘ
avoiding unnecessary data transfer ⓘ bandwidth optimization ⓘ cache revalidation ⓘ conditional requests ⓘ |
| usedIn |
HTTP/1.0
ⓘ
HTTP/1.1 ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: Last-Modified (HTTP header) Description of subject: Last-Modified is an HTTP response header that indicates the date and time at which the origin server believes the requested resource was last changed, enabling caching and conditional requests.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.