Any one of the languages that people have designed for specific purposes, such as representing mathematical ideas or computer programs; all programming languages are formal languages.
An instruction that causes the Python interpreter to display a value on the screen.
A reserved word that is used by the compiler to parse a program; you cannot use keywords like if, def, and while as variable names.
A special symbol that represents a simple computation like addition, multiplication, or string concatenation.
To simplify an expression by performing the operations in order to yield a single value.
Information in a program that is meant for other programmers (or anyone reading the source code) and has no effect on the execution of the program.
A list of the functions that are executing, printed when an exception occurs.
A requirement that should be satisfied by the function before it ends.
One of the operators that compares its operands: ==, !=, >, <, >=, and <=.
One of the operators that combines boolean expressions: and, or, and not.
A recursion that doesn’t have a base case, or never reaches it. Eventually, an infinite recursion causes a runtime error.
A programming pattern that uses a conditional statement to check for and handle circumstances that might cause an error.
A loop in which the terminating condition is never satisfied.
A statement that calls a method.
A test case that is atypical or non-obvious (and less likely to be handled correctly).