Wolfram Language Fast Introduction for Programmers
About the Wolfram Language »

Interactive Usage

The Wolfram Language is interpreted, meaning any piece of code can be run immediately. Java code must be compiled before execution, making truly interactive programming impossible.

The Wolfram Language is interpreted, meaning any piece of code can be run and tested immediately, similar to how you would use Python's interactive shell. Using % in the Wolfram Language works like _ in Python, retrieving the most recent output.

In a Wolfram notebook on the desktop or web, just type an input, then press
SHIFT+ENTER to compute:

In[1]:=
X
Out[1]=
In[2]:=
X
Out[2]=

In[n] and Out[n] label successive inputs and outputs. You can refer to the most recent output as %—though it’s usually better to define a variable.