The HTTP GET method is the default request retrieval action of the HTTP protocol. For example, the same than RETR in FTP.
GET is the primary mechanism of information retrieval.
A payload within a GET request message has no defined semantics; sending a payload body on a GET request might cause some existing implementations to reject the request.
The response to a GET request is cacheable; a cache MAY use it to satisfy subsequent GET and HEAD requests unless otherwise indicated by the Cache-Control header field (Section 5.2 of RFC7234) See HTTP - Cache (Cache-Control Header, Bursting, )
A get can be conditional if the response was cached.