Coercion in JavaScript refers to the automatic conversion of values from one type to another. This can occur in two ways: implicit coercion and explicit coercion. Implicit coercion happens automatically when a value of one type is used in a context that requires a different type. For example, when a number is added to a string, JavaScript will implicitly convert the number to a string so that the two values can be concatenated. Explicit coercion happens when a type conversion function is used to convert a value from one type to another. JavaScript provides three main type of conversion functions: Number, String, and Boolean. These functions can be used to explicitly convert values from one type to another. It's important to understand coercion in JavaScript because it can lead to unexpected results if you're not aware of it. Therefore, it's best to use explicit type conversion when you need to ensure that a value has a specific type.