A primitive is a built-in function or operator which is a core part of the language. It is represented by a glyph, which it may share with another primitive. Special syntax like Assignment (
←) and Branch (
→) can also be considered primitives, though they do not abide by APL's regular syntax. Similarly, special constants like Zilde (
⍬) and Dyalog APL's Root namespace (
#) are sometimes called primitives.