A [store object] produced by a [store derivation].
  See [the `outputs` argument to the `derivation` function](@docroot@/language/derivations.md#attr-outputs) for details.


- [output path]{#gloss-output-path}

  The [store path] to the [output] of a [store derivation].


- [output closure]{#gloss-output-closure}\
  The [closure] of an [output path]. It only contains what is [reachable] from the output.

- [deriving path]{#gloss-deriving-path}

  Deriving paths are a way to refer to [store objects][store object] that might not yet be [realised][realise].

  See [Deriving Path](./store/derivation/index.md#deriving-path) for details.

  Not to be confused with [derivation path].

- [deriver]{#gloss-deriver}

  The [store derivation] that produced an [output path].

  The deriver for an output path can be queried with the `--deriver` option to
  [`nix-store --query`](@docroot@/command-ref/nix-store/query.md).

- [validity]{#gloss-validity}

  A store path is valid if all [store object]s in its [closure] can be read from the [store].

  For a [local store], this means:
  - The store path leads to an existing [store object] in that [store].
  - The store path is listed in the [Nix database] as being valid.
  - All paths in the store path's [closure] are valid.


- [user environment]{#gloss-user-env}

  An automatically generated store object that consists of a set of
  symlinks to “active” applications, i.e., other store paths. These
  are generated automatically by
  [`nix-env`](./command-ref/nix-env.md). See *profiles*.

- [profile]{#gloss-profile}

  A symlink to the current *user environment* of a user, e.g.,
  `/nix/var/nix/profiles/default`.

- [installable]{#gloss-installable}

  Something that can be realised in the Nix store.

  See [installables](./command-ref/new-cli/nix.md#installables) for [`nix` commands](./command-ref/new-cli/nix.md) (experimental) for details.

- [Nix Archive (NAR)]{#gloss-nar}

  A *N*ix *AR*chive. This is a serialisation of a path in the Nix
  store. It can contain regular files, directories and symbolic
  links.  NARs are generated and unpacked using `nix-store --dump`
  and `nix-store --restore`.

  See [Nix Archive](store/file-system-object/content-address.html#serial-nix-archive) for details.

- [`∅`]{#gloss-empty-set}

  The empty set symbol. In the context of profile history, this denotes a package is not present in a particular version of the profile.

- [`ε`]{#gloss-epsilon}