GENSYM
Outputs a unique word each time it is invoked. The words are of the form G1, G2, etc. This is typically used to dynamically generate variable names.
MAKE GENSYM 1 SHOW :g1 1
MAKE GENSYM 1 SHOW :g1
MAKE GENSYM "Hello SHOW :g2 Hello
MAKE GENSYM "Hello SHOW :g2