Conditional Statements

Conditional statements (also called branching) allow a program to make decisions.
They control which part of the code is executed based on whether a certain condition is true or false.
In programming, this decision-making process is a core part of control flow.

What Is a Conditional?

A conditional evaluates a condition—an expression that results in either true or false.

This condition can involve:

Comparison operators
Used to compare two values
Examples: >, <, >=, <=, ==, !=
Logical operators
Used to combine or negate conditions
Examples:
- and, or, not
- &&, ||, !
Function results
Conditions can be based on values returned by a function
Mathematical expressions
Conditions can include arithmetic calculations that evaluate to a value

Based on the result, the program decides which code to run.

Conditional Logic and “If–Then”

If you are familiar with basic logic or mathematics, you may recognize the idea of implication:

If a condition is true, then an action is performed.

This idea is directly applied in programming using conditional statements such as:

if
if else
else if
switch

How Conditionals Work (Conceptually)

A conditional follows this general pattern:

If condition A is true → execute block A
Else if condition B is true → execute block B
Else → execute a default block

In other words:

one condition is tested
the program chooses a path
only the matching path is executed

Why Do We Need Conditionals?

Conditionals are used to:

make decisions in a program
handle different situations
control program behavior

They help answer questions like:

Is this value valid?
Has the user met a requirement?
Should the program continue or stop?

At the core, conditionals work with boolean values: true or false.

Types of Conditional Statements

In this section, conditional logic is introduced step by step:

If — execute code when a condition is true
Else — execute alternative code when the condition is false
Else If — handle multiple conditions
Nested If — conditionals inside other conditionals
Switch — an alternative way to handle multiple choices

Each type builds on the previous one.

Summary

Conditionals control the flow of a program
They execute code based on conditions
Conditions evaluate to true or false
Conditional logic is essential for decision-making

Understanding conditionals is a key step toward writing dynamic and intelligent programs.