Type Conversion in JavaScript

JavaScript is loosely typed, meaning variables can hold any type and types can change. Type conversion (or coercion) is the process of converting a value from one type to another.

There are two kinds: implicit (automatic by JS) and explicit (manual by the developer).

Implicit Conversion (Coercion)

JavaScript automatically converts types in certain operations, especially with the + operator or loose equality (==).

Loose vs Strict Equality

== allows coercion, === requires same type and value.

Explicit Conversion

Use built-in functions to convert types manually.

• String() or .toString() – to string
• Number() or parseInt/parseFloat – to number
• Boolean() – to boolean

Truthy and Falsy Values

In conditions, values are coerced to boolean. Falsy values become false:

• false, 0, "", null, undefined, NaN

Everything else is truthy.

Common Pitfalls

Unexpected coercion can cause bugs. Prefer explicit conversion and strict equality (===).

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