Variable

Variable are:

  • Storage location that have a name
  • Storage location that have a name
fruit = 'apple'
fruit = 'orange'

* Pick variable name that represent data that variable will hold

Valid Variable Names

  • Case sensitive. (Case matters!)
    • Fruit and fruit are different variable
  • Must start with a letter.
    • Can contain numbers.
  • Underscores allowed in variable names
  • Not allowed: + -
first3letters = 'ABC'
first_three_letters = 'ABC'
firstThreeLetters. = 'ABC'

* Pick variable name that represent data that variable will hold

Reserved Keywords

False def if raise None del import return True elif in try and else is while as except lambda with assert finally nonlocal yield break for not class from or continue global pass

*** Function name also not recommend

Example

*** Function name also not recommend

Data Type

Basic Data Types

  • Numeric
    • Integer
    • Floating point
  • Boolean
  • String

Composite Data Types

  • List
  • Tuple
  • Dictionary
  • Set

Numbers

  • Use numbers directly in your source code
  • Do not use quotation marks as they are for strings.
integer = 42
float = 4.2
a = b = c = d = 0.0

* Pick variable name that represent data that variable will hold

Example

Boolean

A Boolean variable can reference one of two values: True or False. Boolean variables are commonly used as flags, which indicate whether specific conditions exist.

hungry = True
leepy = False

Example

String

Strings

  • Represent text
  • Surrounded by quotes
fruit = 'apple'
fruit = “apple”
string1, string2, string3 = '', 'Knife', 'Hammer Dance'

* Strings are start with ' or " and end with 'or "

Using Quotes within Strings

sentence = 'She said, "That is a great tasting apple!" '
sentence = " That's a great tasting apple! "
double = "She said, \"That 's a great tasting apple! \" "
single = 'She said, "That\'s a great tasting apple! " '