This article will help if you want to know the more in-depth features of Pro-Tools such as understanding Channels, Plug-ins, Elastic Audio and Rewire. These videos refer to Pro-Tools First but are also relevant to Pro-Tools.
Where can I find Pro Tools | First?
GETTING STARTED
CHANNELS
PLUG-INS
ELASTIC AUDIO
REWIRE
For further help with Pro Tools First, please see Avid's help pages here.