JavaScript runs on a single thread. Give it a heavy task, like resizing a large photo before uploading it, and the page freezes until it finishes.
Web Workers solve this by running that work on a second thread. In this article for Tighten, I cover how they work, their two main limitations, how they differ from Service Workers, and how to use one to resize and compress images in the browser before they reach your server.
Read the full article here:
