Don't worry about him,
Timmcat... he's just showing off
An example of a symlink in plain English would be the setup I have on my Mac which streams my iTunes library over the web.
Instead of having to place a duplicate of my iTunes library on the server (and at 10-odd gigabytes it's a bit hefty to be making copies all over the place), the symlink arrangement lets me keep the existing iTunes library folder where it is, creating a kind of 'metaphor' or pointer, if you will, from the music to the server.
This also has the advantage of letting me keep my music safe and sound in a secure area of the Mac, rather than risking it on the server.
Hope that's as clear as mud!