[Model Aspect] Container basics [Linked Data Platform (LDP)] 
A container has a URI where you can start interacting with the container, at the most basic level you can GET a list of members, and for containers with many members it is likely the response is broken into pages. Through HTTP HEAD/OPTIONS introspection, a client can learn which HTTP verbs are permitted on this. Since LDP containers are described using RDF constructs, a LDP server may allow clients to POST the representation of the container to create it. Need: How are the acceptable content-types communicated via HTTP headers? Alternative: Before asking 'how' acceptable content-types are communicated, we need to agree that doing so is required (should it be in-scope for LDP - part of ISSUE-21 perhaps). In the simplest case, once the client "knows" it is dealing with a conformant LDP Container it does know (at least) that Turtle is supported. If communicating supported content-types is in-scope, then a syntax needs to be defined (either new, or re-used). Potential re-use choices might include (and these are not necessarily mutually exclusive, although to keep clients simple it would help to have at least one required method if it is in-scope): atom:accept predicate(s) on a container Link: <>; rel="self"; type="one acceptable media type value" Linking itself to a POWDER document - I don't see any POWDER syntax covering media types, but it might be possible to re-use atom:accept in this context. Aside: If we do place it in-scope, we have the same question about members, so it might be that we talk about this introspection at the LDPR level and let LDPCs "inherit" it from LDPRs. LDPRs might leave everything optional, and LDPC requires one particular method while allowing others, for example.