Variable symbols must begin with an & followed by an alphabetic character and, optionally, up to 61 alphanumeric characters. Variable symbols can be used in macro processing and conditional assembly instructions, and to provide substitution in machine and assembler instructions. They allow different values to be assigned to one symbol. A complete discussion of variable symbols appears in How to specify macro definitions.

&VARYINGSYMABC      &@ME
&F346944            &A
&EASY_TO_READ