true -> <stdout>
true also outputs the term "true":
» true true
However you can suppress that with the silent flag:
» true -s
-ssilent - don't output the term "true"
!(not): Reads the STDIN and exit number from previous process and not's it's condition
falsedepending on whether multiple conditions are met
false: Returns a
if: Conditional statement to execute different blocks of code depending on the result of the condition
falsedepending on whether one code-block out of multiple ones supplied is successful or unsuccessful.