Variables in Python

Definition

• A variable is a container for a value.
• Each variable should have a unique name.

Data Types

There are four basic data types discussed:

1. Strings
2. Integers
3. Floats
4. Booleans

1. Strings

• A string is a series of text which can be enclosed in double or single quotes. (Preference: double quotes)
• Example of a string variable: first_name.
• To assign a variable: use the assignment operator (=).
• Print a string variable using a print statement without quotes.
• Use f-strings for formatted output:
  • Syntax: f"{variable}"
  • Example: print(f"Hello, {first_name}")

2. Integers

• An integer is a whole number.
• Example: A person's age (e.g., age = 25).
• Print an integer variable without quotes:
  • Example: print(f"You are {age} years old.")
• Integers can be used in arithmetic expressions.

3. Floats

• A float is a floating point number that includes a decimal portion.
• Example: Price (e.g., price = 10.99).
• Print a float variable:
  • Example: print(f"The price is ${price}")
• Other examples include GPA (e.g., gpa = 3.2) and distance (e.g., distance = 5.5).

4. Booleans

• A boolean is either True or False.
• Example: is_student = True.
• Booleans are often used within if statements.
  • Example:

    if is_student:
        print("You are a student.")
    else:
        print("You are not a student.")
    

Examples of Booleans

1. is_for_sale - checks if an item is for sale.
2. is_online - checks if someone is online.

Conclusion

• Variables are a reusable container for a value.
• Four basic data types: Strings, Integers, Floats, and Booleans.

Assignment

• Post four variables in the comments section:
  1. A string
  2. An integer
  3. A float
  4. A boolean
• Aim for unique examples.