We provide web hosting 

When you are search for a web host for your website and doing research for selecting your web host, you may find that almost all of the web hosts are providing:

• Unlimited web space
• Unlimited bandwidth
• Unlimited domains hosting

Unfortunately it’s not possible for a web host to provide unlimited web hosting as every server and data center has limits.

As most people are using very less space for their websites, and as most of the websites are database driven the uses of web space is getting decreased.So if  a web host provider have a space of  200 GB hard disk and 100 clients on that server; they should not offer more than 0.5 gb of space but they know that even that amount space will not be used. There will be a huge amount of free space if 100 general user clients use them.

A very common way to limit space is introducing the concept of inodes. If you check properly all unlimited shared hosting plan have limited inodes. And this inode is nothing but the number of files. Most CMS have almost 4000-10000 files and if you are using too many images then inode may be a critical factor while choosing a web hosting.

I have a website with 100 – 200 web pages and about 100 images which is using merely a 300 MB of web space.

This marketing tactic (which is what it is) has a name – overselling. Overselling simply means to sell more than you actually have. Due to the competitive nature of the web hosting industry web hosts have been increasing the amount of space advertised in order to gain more market share. Web hosts that offer advertise unlimited hosting are doing so with the hopes that the majority of people on the server won’t use much space. The truth is that the majority of people using shared hosting are not likely to use/need very much space so that’s another reason why it’s so common to sell unlimited offers.