If you have an apache server, you should be familiar with google analytics, awstats or other good ways to see statics about the use of your site, some of this services are free some others not, and they present you with a lot of good info, but the most of them are not in real time, you may want to see some statics in realtime about your site.
A real good tool for this is apachetop, which will run on your server and present you with a some real time information about your site load, and the pages being seen at a given moment.

Maybe almost all of Linux users have used top to check how your system is doing, the running processes and use of CPU or the use of Memory.

But top lacks in some functionality that could the useful, for example, when it runs out of space in our screens it just do not show the rest of the processes.

Here is where htop appears.

When you need to see the running processes on your Linux in real time, you have top as your tool for that.

top also displays other info besides the running processes, like free memory both physical and swap

Usage

top [options]