LEGO models and bricks are measured in a fanciful unit
called the stud rather than in inches or centimeters. One
stud equals the width of the smallest brick, which is 8 mm
wide. We’ll even use the stud to measure LEGO pieces that
aren’t bricks, like shock absorbers and axles.
When the unit of measurement for a LEGO piece is
omitted, you can safely assume that it is the stud—for
example, a 1×1 brick, a 2×2 tile, and so on. This is how
we’ll refer to pieces in this book.