Chapter 2: Software Development, Data Types, and Expressions

data type

consists of a set of values and a set of operations that can be performed on those values 

literal

the way a value of data type looks to a programmer

int

float

data types that represent numbers

string literal

simply text written directly in your code, usually wrapped in quotes

Empty string (' ' ) (" ")

A string that contains no characters.

think of it like an empty box

String Concatenation

join two or more strings to form a new string using the concatenation operator +

variable

A memory location, referenced by an identifier, whose value can be changed during execution of a program.

symbolic constants

Programmers use all uppercase letters for the names of variables that contain values that the program never changes

STANDARD_DEDUCTION

assignment statement

A method of giving values to variables.

Defining or initializing

Python interpreter first evaluates the expression on the right side of the assignment symbol and then binds the variable name on the left side to this value

variable references

The process whereby the computer looks up and returns the values of variables.

program comments - block comments

Text in a program that is not executed as code, but informs the reader about what the code does.

docstring

A sequence of characters enclosed in triple quotation marks (""") that Python uses to document program components such as modules, classes, methods, and functions.