To supplement what others have said about Emacs the editor and its relation to Emacs Lisp, Emacs as an editor works this way:
Keys you hit or mouse actions you make are bound to interactive Emacs-Lisp functions called commands.
More precisely, key sequences are bound to commands. A key sequence might be just hitting one keyboard key. Or it might be hitting multiple keys, either together as a chord (using modifier keys such as Control and Shift) or sequentially.
Key sequences that are not bound to commands are either ignored or have a default effect - typically raising an error telling you that that key sequence is not bound.
It is worth repeating that this is pretty much all that Emacs does. Even when you type the letter
a by hitting the
a key, to insert an
a in a text buffer, an Emacs command is invoked: the command named
self-insert-command. In a nutshell: Everything you do in Emacs amounts to invoking Lisp functions by hitting keys.
The keyboard keys that you typically think of as entering text (
%, etc.) are generally bound to command
self-insert-command in contexts where text insertion makes sense.
In other contexts, the same key might be bound to another command. For example, in the Emacs directory editor (mode Dired), the key
a reads a file name and then visits that file. In still other contexts, the same key (e.g.
a) might not be bound, and Emacs tells you so when you hit it.
So you can think of Emacs as an interpreter of Emacs Lisp. Or you can think of Emacs as a bunch of bindings of keys to Emacs-Lisp functions - that is, you can think of Emacs as Emacs Lisp with some keyboard "hooks".