Question

What does the 'use strict' do in JavaScript?

A. Enforces a stricter set of rules for JavaScript, catching common coding mistakes and "unsafe" actions.
B. Declares a variable with the name "strict" and assigns it a boolean value.
C. Enables lenient mode, allowing more flexibility in JavaScript code.
D. Disables all error messages and exceptions in JavaScript code.

Answer 1

The 'use strict' statement in JavaScript activates a stricter parsing and error handling of your code, which aids in catching mistakes and preventing unsafe actions. It is a beneficial practice for writing more secure and robust JavaScript code.

Step-by-step explanation:

The 'use strict' statement in JavaScript enforces a stricter set of rules for the language, flagged as Option A. When 'use strict' is included at the beginning of a script or function, it helps programmers avoid common pitfalls in JavaScript by catching common coding mistakes and preventing 'unsafe' actions such as creating global variables by accident. This strict mode helps in avoiding errors that might otherwise go unnoticed, leading to possible issues with the code's execution.

Strict mode also makes debugging easier because it stops the execution of JavaScript when it encounters an error that under normal circumstances might have been ignored or would have failed silently. As a result, it is beneficial for developers to use strict mode to write more secure and robust scripts.