Name

Whereas a primitive is a word defined by the system, a name is a word defined by you. The primitive =. defines a name.

v =. 23

The sentence can be read as v is 23. The word =. is called copula (another good English language term). The name v is defined as the number 23 and can be used in other sentences.

   5 + v
28

Unlike a primitive, a name can be redefined.

   v =. 45
   5 + v
50

The system does not display the result of the sentence when it begins with a copula. A sentence that contains only a name shows a display form of the definition of the name.

   abc =. 123
   abc
123

You can give anything a name. For example, you could give a name to the verb + .

   plus =. +
   23 plus 45
68

The preferred way to read abc =. def is: abc is def or abc is defined as def. However, borrowing from other computer languages, it is also common to say: abc is assigned the value def or the value def is assigned to abc.