HostGator is one of the largest web hosting services around today - over 4 million websites hosted by them. They offer a fairly focussed range of products and services for webmasters, including Reseller hosting (a hosting account that allow you to host other accounts), VPS (Virtual Private Server) hosting and dedicated server hosting. I've been involved in web hosting services before and am still amazed at companies like HostGator that can offer competitve hosting for less than $5 a month - I know, we couldn't.
For most people, you and me, their basic web hosting package is more than sufficient. They have unlimited disk space and bandwidth as well as 24/7 technical support (very important) and a 99.9% uptime gaurantee (also very important). All this for $4.95 per month is not really something that can be improved upon as far as I can tell.
Hostgator's success comes down to the fact that they offer fewer services, but what they do offer, they do really well - and they've won plenty of awards in the process. Kind of like going to a restaurant that only serves steak and chips, but they're absolutely the best steak and chips in town, so the place is always full.
With a 45 day money back gaurantee, there's really nothing stopping you giving them a try if you want to host your own website. They even have a website building service for you to try out.