# Data Structures Triplet graphs similar to linked data fragments with envelopes. decoupling content addressing from versioning - Merkel DAGs - Envelopes - Versioning - Typed objects with formatting ## Containers - Packets of LD-triplets that contain - Hash of triplets - Encryption Info (if applicable) - Permissions scope - Signature - Anything that can be directly referenced without local qualifier is a container. - Triplets within a container can be referenced with the [query syntax](qlocation) - Containers also behave like "feeds" - Eg. one might put their blog posts in `@user:blog` or - The account identifier is the top-level container. - Ordering: - Every triple within a scope is ordered by default by the time it is declared - A container can declare its ordering (see {term}`Container`) - Naming: - Each container intended to be directly referenced SHOULD contain a `name` so it can be referenced w.r.t its parent: `@:` - Each container can also be indicated numerically - Identity: Each container is uniquely identified by the hash of its contents and the hash of the account identifier. - Format: A container can specify one or several ways it can be displayed - Capabilities: A container can specify different capabilities that another account can take (eg. "Like", "Upvote", "Reply") - Capabilities should also contain a permissions scope, if none is present, the global scope is assumed. - Since Identities are just a special form of container, they too can advertise different actions that they support with capabilities. Re hashing a graph: the container always has one root node that is the container's identity from which a graph traversal starts. A {index}`Merkle DAG` is then constructed starting from the leaves. ## Triplets - Triplet format - Objects require a shortname that can be hierarchically indexed from - Types/Schema - Including intrinsic notion of nesting - every object can have blank/positionally indexed children - every triple can have blank/positionally indexed "qualifiers" like RDF-star or wikidata's qualifiers. ## Schema ## Codecs See IPLD Codecs and Linked Data Platform spec Means of interacting with binary data. Describes - Format - ## Versioning - A given container has an identity hash from its first packing - A given triple can be contained by