If It Happens... Else Do This! Understanding Conditions in JavaScript

Today I learned about conditional statements in JavaScript. These statements are the building blocks for decision-making in any program. I understood how we can control the flow of the program based on certain conditions using if, else, else if, and even nested if blocks.

What is a Conditional Statement?

Conditional statements let the program decide what to do next based on whether a condition is true or false.

In JavaScript, we use these:

• if – checks a condition and runs the code if it’s true
• else – runs when the if condition is false
• else if – checks multiple conditions in order
• nested if – an if inside another if, used for complex logic

Flowchart: How Conditional Statements Work

        [Start]
           |
       [Condition]
        /      \
     True     False
     /           \
[If block]     [Else block]
     |
[Else if block] (optional)
     |
    [End]

Problem I Solved: Grade Calculator

Problem Statement:

Write a program to accept a student’s mark and print the grade based on the mark.

Code:

let marks = 85;

if (marks >= 90) {
  console.log("Grade A");
} 
else if (marks >= 80) {
  console.log("Grade B");
} 
else if (marks >= 70) {
  console.log("Grade C");
} 
else if (marks >= 60) {
  console.log("Grade D");
} 
else {
  console.log("Grade F");
}

• The program checks one condition at a time.
• Once a condition is true, it prints the corresponding grade and stops checking further.
• If none match, it goes to the final else block (Grade F).

Ask Yourself: What Are the Alternatives?

Can you solve the same problem using any of these?

• Ternary Operator
• switch(true) statement
• Function-based logic
• Nested if

Challenge for You:

Try rewriting this same grade logic using one of the above methods and see which is shorter or easier to understand!

What I Learned

Conditional statements help in making programs dynamic and responsive. Whether it's grading students, checking login info, or greeting users based on time — they are used everywhere. I’ll keep practicing to get more confident with different structures.