How Stack Overflow questions and answers are available in Google search within a minute after posting? Which technology is being used for this both from Stack Overflow and Google side?
I know 2 points which affects:
- Site with high Page Rank(PR), currently Stackoverflow is having 7/10 pagerank.
- Site which is being updated very frequently is crawled more quickly, indirectly it means that particular site is having latest/updated data, and in this case Stackoverflow is getting infinite number of questions/answers at every second.
If you check in this site http://www.prchecker.info/check_page_rank.php the Page Rank for SO is very high (7). So i guess Google will have algorithm tweaked to index these types of (Famous) sites fast and show that in results quickly.