Anyone in search of web hosting is inundated with offers from web hosts that promise "unlimited" web hosting. According to the advertising, the number of websites that can be hosted in a single account is unlimited, while the amount of disk space these websites take up is also unlimited. Besides this, the advertising suggests these websites can use bandwidth without any suggestion of restraint. While our logic dictates that no resource, whatever it is, can ever be infinite, our desire for a "great deal" or an "absolute bargain" is often strong enough to overshadow any commonsense we might have.
So how do hosts offer "unlimited" hosting, without it actually being "unlimited"?
Restricting usage is a particular way hosts avoid needing to be able to genuinely offer unlimited capacity. Many "Terms of Service" and "Service Level Agreement" documents are littered with phrases that support the concept of resources being unlimited, yet at the same time also hint at the reality of the situation. One caveat is what web hosting can be used for.
As far as disk space is concerned, agreements tend to dictate that a host's servers can only be used to host websites. However, if a server genuinely offers unlimited resources, an account holder should effectively be able to use this capacity as a "cloud" to store pictures, videos, etc. Clearly though this is not the case.
Unlimited resources - unless other websites need them
As far as other server resources are concerned, again usage is unlimited except when usage "impacts" other websites hosted on a server. CPU usage is a good example of this. Agreements allow single websites unlimited access to processing power except to the point where other websites are not able to utilize processing power. Theoretically, if no other websites utilized any processing power, it would all be available to your website(s). But as that is never going to be the case, offering unlimited CPU is meaningless. This is obviously equally as true as far as RAM is concerned. Indeed, all websites on a server will also have to use bandwidth.
Unlimited resources are available - but using a drip feed
Another caveat that is often dropped into agreements is the inability a customer has to utilize unlimited resources except in a staged fashion - meaning a website should grow rather than be a huge affair that utilizes a lot of resources from the outset. For example, if Facebook suddenly decided that it wanted to move its massive framework to an unlimited shared hosting account, the immediate utilization of such massive amounts of resources that would require would mean the web host would not allow Facebook onto its servers. Just how fast a website can grow is generally not stated in agreements, and so it is up to the discretion of a web host to decide when a site is using too many resources.
Check your agreements
Obviously, it pays to check the terms of your web hosting agreement to get a full picture of what unlimited will mean to you. But as I have said above, agreements are often written in a "Newspeak" fashion where unlimited resources are available, until they are not. As such the fine print is not just difficult to read, it is often difficult to understand.
Another route is to ask directly. Below is an actual question I sent a leading and well-known web host's customer support. The answer, I thought, got to the point fairly directly:
Question: "When you can use unlimited space / domains / bandwidth, what does this really mean? At what point would THISWEBHOST consider an account using too much of an accounts available resources?"
Answer: "As per our Terms Of Service at
http://THISWEBHOST.COM/tos.shtml you are allowed to have up to 250,000 INodes (Files and Folders) and you are allowed up to 25% of the systems resources for no more than 90 seconds. Basically as long as your account is not causing issues with the server, you will be fine. Unfortunately there is no way to tell what the exact limit is because every account is different."
Kudos to whoever sent that!
Where does that leave me?
I once had a website taken off-line because a programmer has messed up a script he had designed for me, and the program was making multiple queries to the server. Luckily, I wasn't dependent on that site for my income. Had that site been "mission critical" as far as my business was concerned, I would have been immediately out of pocket. So let your commonsense kick in again.
If you have a site (or sites) that genuinely need unlimited resources, chances are you are making money. If you want to risk your income (or your business) to your web host's interpretation of what "unlimited" means, then go ahead - otherwise pay for unlimited resources.
Depending on the size of your site(s), Virtual Private Server (VPS) hosting, or even a dedicated server can mean that you can rest at ease in the knowledge your the resources available to keep on making you money are available to your site(s)! Alternatively, choose a cloud account where you pay for what you use and if you use need more resources than usual, they are available to your site whenever they are required.