You show up at the client’s door and begin asking for access to their system.  They respond with, “What kind of access do you need?”  When you tell them “Web and 2-tier.”  They give you the look that indicates your third head is showing.

Here’s a short you-tube that lays out the differences for them: https://www.youtube.com/watch?v=3YIubn0QLFg

It riles them to believe, that you percieve, the webs they weave.