WordPress

WordPress is currently one of the most used Content Management Software  packages.

It allows technical and non technical people to add / change content on a website through an interface that looks like Microsoft Word or for the more technical you can program using HTML code.

The software is Open Source and is always being updated and improved.

Plugins can be installed (they are like Apps on an Ipod ) to carry out specific requirements and most of them are free but they do look for a small donation.