1.2.6 Sequences of Operations
In doing a calculation with Mathematica, you usually go through a sequence of steps. If you want to, you can do each step on a separate line. Often, however, you will find it convenient to put several steps on the same line. You can do this simply by separating the pieces of input you want to give with semicolons.
Ways to do sequences of operations in Mathematica.
This does three operations on the same line. The result is the result from the last operation.
In:= x = 4; y = 6; z = y + 6
If you end your input with a semicolon, it is as if you are giving a sequence of operations, with an "empty" one at the end. This has the effect of making Mathematica perform the operations you specify, but display no output.
Putting a semicolon at the end of the line tells Mathematica to show no output.
In:= x = 67 - 5 ;
You can still use % to get the output that would have been shown.