Operators & Conditionals

#python #tutorial #beginners #programming

Arithmetic operators

These perform basic math: +, -, *, /, % (modulus - the remainder after division), and ** (exponent).

a = 150
b = 200
c = 300
d = 10
e = 3

total = a + b + c   # 650
diff = b - a         # 50
rem = d % e           # 1  (remainder of 10 ÷ 3)
div = c / d           # 30.0
power = e ** 2        # 9

Comparison operators

These compare two values and always evaluate to a boolean (True or False): == (equal to), != (not equal to), >, <, >=, <=.

age = 18
print(age == 18)   # True
print(age != 20)   # True
print(age >= 21)   # False

The most common beginner mistake here is confusing = (assignment) with == (comparison) - age = 18 sets the value; age == 18 checks it.

Logical operators

These combine multiple conditions: and (both must be true), or (at least one must be true), not (flips a boolean).

age = 20
has_id = True

if age >= 18 and has_id:
    print("You can enter")

Conditionals: if, elif, else

Conditionals let a program make decisions - running different code depending on whether a condition is true:

score = 72

if score >= 90:
    print("Grade: A")
elif score >= 75:
    print("Grade: B")
elif score >= 60:
    print("Grade: C")
else:
    print("Grade: F")

Python checks each condition top to bottom and runs the first block whose condition is True, skipping the rest - elif (else-if) lets you chain as many conditions as needed, and else catches anything that didn't match.

Practical examples

Combining comparison and logical operators inside a conditional - checking eligibility against two conditions at once:

age = 19
id_present = True

if age >= 18 and id_present == True:
    print("You can drive")
else:
    print("Not eligible yet")

A slightly more layered example, using elif to categorize a value into ranges:

temperature = 28

if temperature > 30:
    print("It's hot")
elif temperature >= 20:
    print("It's warm")
else:
    print("It's cold")

What I understood from this

The distinction that mattered most here was between comparison operators (which produce a boolean answer to a single question) and logical operators (which combine several of those boolean answers into one final decision). A condition like age >= 18 and has_id only reads cleanly once you see it as two separate True/False questions being joined by and - Python evaluates each side independently first, then combines them. Once that clicked, writing more complex conditions stopped being about memorizing operator symbols and became about breaking a real-world rule ("you can drive if you're old enough and you have ID") into the exact boolean pieces Python needs.

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