298 Glossary
module A file or set of files with related variables, functions,
and classes that can be reused in other programs.
nested loop A loop inside another loop.
object A variable containing information about a single instance
of a class, such as a single sprite from the Sprite class.
operator A symbol or set of symbols that represents an action
or comparison and returns a result, such as +, -, *, //, <, >, ==,
and so on.
parameter An input variable to a function, specified in the
function’s definition.
pixel Short for picture element, the small dots of color that make
up images on a computer screen.
program A set of instructions written in a language computers
can understand.
pseudorandom A value in a sequence that seems to be random
or unpredictable, and is random enough to simulate rolling dice or
f lipping coins.
random numbers An unpredictable sequence of numbers
evenly distributed over a certain range.
range An ordered set of values between a known start and end
value; in Python, the range function returns a sequence of values,
such as 0 through 10.
RGB color Short for red-green-blue color, a way of represent-
ing colors by the amount of red, green, and blue light that can be
mixed to re-create each color.
shell A text-based command line program that reads commands
from the user and runs them; IDLE is Python’s shell.
sort To put elements of a list or array in a certain order, such as
alphabetical order.
string A sequence of characters, which can include letters, num-
bers, symbols, punctuation, and spacing.
syntax The spelling and grammar rules of a programming
language.