This is the free, ‘light’ version of SharePoint available in 2010 and 2013. It is the core functionality of the platform. The licenses are available with certain SQL Server licenses, or you can get them hosted in the cloud from some non-Microsoft companies.
The next version up is Standard, and then up from that, Enterprise. More and more functionality gets added as you go up the licensing chain – naturally so does the price.
We are firm believers that if you can’t get value from Foundation, you won’t easily get value from Enterprise. So get the basics right first. The proof is in the pudding because the very first SharePoint Specialist of the Year for South Africa built their entire intranet on SharePoint 2010 Foundation with no 3rd tools in sight. It can be done!