!!! Overview
[{$pagename}] is defined by for our use as an [Entity] [authorized|Authorization] to act on behalf of another. (Which is [Delegation])So we could say a [permission] has been [delegated|Delegation] by an [Entity] to the [{$pagename}]

[Proxy Servers]  are probably the most often used instances of a [Proxy] for most of our purposes.

!! Proxy is an [Observer]
Proxy and therefore [Proxy Servers] are by definition an [Observer] and a potential [Man-In-The-Middle]

!! [RFC 2616]
[RFC 2616] defines [{$pagename}] as an intermediary program which acts as both a [server] and a [client] for the purpose of making requests on behalf of other clients.

Requests are serviced internally or by passing them on, with possible translation, to other servers. A proxy [MUST] implement both the [client] and [server] requirements of [RFC 2616]. 

A "[Transparent Proxy]" is a [{$pagename}] that __does not modify__ the [request] or [response] beyond what is required for [{$pagename}] [authentication] and [identification]. 

A "non-transparent proxy" is a [{$pagename}] that modifies the [request] or [response] in order to provide some added service to the [user-agent], such as group annotation services, media type transformation, protocol reduction, or anonymity filtering. Except where either transparent or non-transparent behavior is explicitly stated, the [HTTP] [{$pagename}] requirements apply to both types of proxies.

!! More Information
There might be more information for this subject on one of the following:
[{ReferringPagesPlugin before='*' after='\n' }]