Python Variables | learn python

Creating Variables

Unlikely other programming languages, Python has no command for declaring a variable.
When a variable is created the moment you first assign a value to it.

Example

x = 5
y = "John"
print(x)
print(y)
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Variable does not need to be declared with any particular type and can even change type after they have been set.

Example

x = 4 # here x is of type intx = "Sally" # here x is now of type strprint(x)
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Variable Names

A variable can have a short name (like a and b) or a more descriptive name (age, carname, total_volume). Rules for Python variables:
  • A variable name must start with a letter or the underscore characters
  • A variable name cannot start with a number
  • the variable name can only contain alpha-numeric characters and underscores (A-z, 0-9, and _ )
  • Variable names are case-sensitive like (age, Age, and AGE are three different variables)
Remember these variables are case-sensitive


Output Variables

The Python print statement is often used to the output variable.
To combine both text and a variables, Python uses the + character:

Example

x = "awesome"
print("Python is " + x)
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You can also use the + character to add a variable to other variables:

Example

x = "Python is "
y = "awesome"
z =  x + y
print(z)
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For numbers, the + character works like as a mathematical operator:

Example

x = 5
y = 10
print(x + y)
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If you try to combine a string and a number, Python will gives you an error:

Example

x = 5
y = "John"
print(x + y)
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Test Yourself With Exercises

Exercise:

Create a variable named carname and assign the value Volvo to it.
 = ""


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