10 Commonly Made Coding Mistakes in JavaScript and How to Avoid Them

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JavaScript is a versatile and powerful language, but its flexibility can sometimes lead developers into common coding traps. Understanding these pitfalls and how to avoid them is essential for writing clean, efficient, and bug-free code. Below are 10 commonly made coding mistakes in JavaScript and tips on how to avoid them:

1. Using == Instead of ===

• The Mistake: The == operator performs type coercion, which means it attempts to convert the types of variables before comparing them. This can lead to unexpected results, like 0 == false being true.
• The Fix: Always use === for comparisons, which checks both value and type without coercion. Similarly, use !== for non-equality comparisons.

if (value === 0) {  // Correct
  // Do something
}

2. Not Declaring Variables with let, const, or var

• The Mistake: If you fail to declare a variable, JavaScript creates it in the global scope, which can cause unexpected behavior or conflicts between different parts of your application.
• The Fix: Always declare variables using let or const for block scoping, and use var only if…