Tips for golfing in TikZ TikZ is a Latex package used for drawing precise images in Latex documents.  It has a massive specification and a boatload of features that may be useful for graphical-output style questions.

What tips do people have for golfing in TikZ?  As always, tips should be specific to to TikZ (e.g. "Remove comments" is not an answer), and stick to a single tip per answer.
Use \def
\def is an incredibly powerful tool when it comes to golfing.  \def allows you to assign something to a variable.
This can be used simply with the to save a number you may use a bunch of times for instance
\def\x{1456}

Will define 1456 as \x for future use much like saving a variable might in a programming language.
However \def is much more powerful than that, because \def doesn't define a variable it defines a snippet of code to be substituted into the program whenever it is called.
For example say you want to draw some rectangles using \draw  you might write the following code:
\draw(0,0)rectangle(3,4)rectangle(8,0);\draw(2,2)rectangle(3,3);

Using \def this could be written as:
\def\x{)rectangle(}\draw(0,0\x3,4\x8,0);\draw(2,2\x3,3);