This site/page has used all avaialble php

hello,I get this message (# This site/page has used all avaialble php / apache processes allowed on free hosting account) so after one or two minutes my site back to work so could I know why?
and I’ve another question if my visitors will become hundreds will I see more message from this kind or no relation? I mean… the site has used all avaialble php… sorry for my language thanks a lot

If a website suddenly gets a large spike in traffic, we don’t want that flood to harm other websites on the server. Because of that, we restrict how many requests an account can process at a time. If too many people are requesting a page at the same time, you’ll get the error you just saw.

As soon as the requests currently in progress have been handled, the processes are freed up again to handle new requests, and you’ll be able to load pages again.