[Mitman]

I was just wondering how major websites like Facebook, Google, etc. store their information in databases. Is it simply mysql with much more security/complexity or is there some other method for storing such large amounts of data. I am learning PHP/MySQL right now just for fun and to hopefully make a small website sometime in the future.

[Ionut]

Big companies with large databases don't work with MySql or open source databases, but with MSSQL, Oracle, DB2. There are more powerfull, offer a better experience in administration and have the most impresive solutions for two of the most important request nowadays: scalability and high availability.
About Google(as for Microsoft and Amazon) moved its storage in Cloud and, because I am not familiar with this concept, I cannot give you more details, but you can search about Cloud on google.

[AdaHacker]

Ionut, on 15 January 2011 - 04:57 AM, said:

Big companies with large databases don't work with MySql or open source databases, but with MSSQL, Oracle, DB2.

That depends on whether you're talking about large enterprises or large websites. MySQL is actually quite popular with large public-facing websites. For instance, Facebook, Twitter, and YouTube make use of it.

[skyhawk133]

A lot of larger companies like Google and such are using NoSQL type implementations. Google uses what's called "BigTable". You can read up on NoSQL implementations here: http://en.wikipedia.org/wiki/NoSQL

MySQL is quite popular, but it is not what is used by some of the largest sites anymore. It's just not fast enough for the type of processing they have to do.

[Mitman]

Thanks for the replies. They were very helpful and i appreciate the links you gave.