Web hosting is the space where files & contents of a site are kept to make it accessible on the internet. There are some important terms related to web hosting, which you should know clearly before buying any hosting. These are briefly described below.
1. Server PC: The PC where websites are kept is called server PC. Server PC's are usually high-performance PC connected to high speed & reliable internet & are kept running all the time to keep hosted sites up.
2. Disk Space: Disk space is the space on the server PC which is allocated for an account to store web files. Any file you want to publish on the internet should be kept on this space. The required space for a website is same as the total volume of the files, databases, emails etc.
Suppose, You want to host a website which has 200 files, which are 270MB, in volume. The site has a database of 10MB & You want to store up to 30MB's of email then the required space is 270+10+30 = 310MB.