"What is the difference between channel name, channel title, and functional name?"

When publishing a channel you will be asked for a few pieces of information related to the name of the channel:

Channel Name: This is the name that will appear at the top of the channel itself when it's published to a layout.

Channel Title: This is the title used when listing channels available for publishing in the 'Preferences' section.

Functional Name: This is the internal ID used by Academus to identify a channel.  This is used for routing the user to the appropriate help section and should not be changed in any of the default published channels.