How do I save data on a server ("In the cloud")?

I am learning web application development. To save anything on a server, ("In the cloud," like Facebook and Google do) within a web application, do I need to use 开发者_开发问答server side code, or can it be accomplished another way?

A web application typically saves data in a (SQL) database. You could start off with a DB software (mysql, postgres, etc.) running on the same server as your application. As you application scales, you can evaluate other options such as separating out the work load, memcache, etc.