Examples4 available
On the client side, very time-consuming operations should run asynchronously so as to avoid freezing the browser. The best example is the operation of Ajax.
Most of us have, to some extent, experienced being caught in a cycle like this one: Facing the browser, you hit, like you always do, Ctrl-T to open a new tab, type in the first letter of the website you always visit, and hit "enter"... just to see if anything new has happened.