Flash cards
Review the key moves
What is the main idea behind Python Variables?
Lesson checks
Practice each idea before moving on
Short Mimo-style checks built from this lesson's code, terms, and sequence.
Which statement best captures the main point of this lesson?
Put the learning moves in the order that makes the concept easiest to apply.
Variables
Variables are containers for storing data values.
Creating Variables
Python has no command for declaring a variable.
A variable is created the moment you first assign a value to it.
Example
x = 5
y = "John"
print(x)
print(y)Variables do not need to be declared with any particular type , and can even change type after they have been set.
Example
x = 4 # x is of type int
x = "Sally" # x is now of type str
print(x)Casting
If you want to specify the data type of a variable, this can be done with casting.
Example
x =
str(3) # x will be '3'
y = int(3) # y
will be 3
z = float(3) # z will be 3.0Get the Type
You can get the data type of a variable with the type() function.
Example
x = 5
y = "John"
print(type(x))
print(type(y))Single or Double Quotes?
String variables can be declared either by using single or double quotes:
Example
x = "John"
# is the same as
x =
'John'Case-Sensitive
Variable names are case-sensitive.
Example
a = 4
A =
"Sally"
#A will not overwrite a