This example demonstrates a common type coercion issue in JavaScript where the + operator performs string concatenation instead of numerical addition when one of the operands is a string. The bug.js ...

About Unexpected string concatenation in JavaScript function. The function should add two numbers, but it concatenates a number and a string.

toUpperCase () – Converts the entire string to upper case. Note: The concat, match, replace, and search functions were added in JavaScript 1.2. All other functions are available in JavaScript 1.0.