Is the maximum amount of money that an advertiser is willing to pay each time a searcher clicks on a ad?

If you think it’s worth US$. 25 to have someone visit your website, you can set US$0.25 as your max. CPC. You’ll pay a maximum of US$0.25 when a person reads your ad and clicks it, and you pay nothing if they don’t click.

For More Information Please Refer: https://support.google.com/google-ads/answer/2464960?hl=en