Search Efforts

How often do search engines scan the internet for information?

How often do search engines scan the internet for information and update what they've got? No, I meant that how often does the search engine catalogue and update what's online. So if I search for something today - let's say "hungry gorillas" and it turns up 10 results and 3 of those websites are then deleted today, they'll still show up on my search in a few days - how long will it take the search engine to figure out that those 3 websites are no longer online?

Public Comments

1. Every time someone does a search a scan is made.
2. Everytime someone searches for something a scan for what they searched is made. usually what they search for has to be in the html code of a website in the title, keyword, or description. good luck.