Here's code from a previous section that uses variables:

# Gets the user's name and greets them
my_name = "Jason"
user_name = input("Enter your name: ")
print(f"Hello {user_name}, nice to meet you. I am {my_name}.\n")

# Gets the user's age and compares
my_age = 31
user_age = input("Enter your age: ")
difference = my_age - int(user_age)
print(f"I am {difference} years older than you.")

On the first line, "Jason" is saved in a variable. A variable stores a value to be used later in the program. The value can have one of several different data types. Examples of data types are:

• strings - words or sentences wrapped in quotes like "hello"
• integers - whole numbers like 1 or -76
• floats - decimal numbers like 1.5 or 0.006

To create a variable, give it a name, and set it equal to a value using the = operator. Variable names can contain only letters, numbers, and the underscore symbol, and the first character cannot be a number. So variable223 and new_value1 are valid variable names, but 1num and v@r are not. Variables should be all lowercase, and words should be separated by underscores. This is called snake case.

To inject a variable in a string, use an f-string. The line print(f"Hello {user_name}, nice to meet you. I am {my_name}.\n") in the code is an example of an f-string. Put the letter f in front of the quotes, and wrap variables in curly brackets.