2.11 Glossary

Value: One of the basic units of data, like a number or string, that a program manipulates. 
Type: A category of values. The types we have seen so far are integers (type int), floating-point numbers (type float), and strings (type str). Integer: A type that represents whole numbers. Floating-point: A type that represents numbers with fractional parts. String: A type that represents sequences of characters. 
Variable: A name that refers to a value. Statement: A section of code that represents a command or action. So far, the statements we have seen are assignments and print statements. 
Assignment: A statement that assigns a value to a variable. 
State diagram: A graphical representation of a set of variables and the values they refer to. 
Keyword: 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. 
Operator: A special symbol that represents a simple computation like addition, multiplication, or string concatenation. 
Operand: One of the values on which an operator operates. 
Floor division: The operation that divides two numbers and chops off the fraction part. 
Expression: A combination of variables, operators, and values that represents a single result value. Evaluate: To simplify an expression by performing the operations in order to yield a single value. Rules of precedence: The set of rules governing the order in which expressions involving multiple operators and operands are evaluated. Concatenate: To join two operands end-to-end. 
Comment: 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.