What is Rooting?

I am very new to the Smart Phone gadgets so I have no idea what rooting is with a phone.  I do have a background in IT and easily upgraded my Infuse to GB 2.3.6 with Odin

i am going to suggest doing a little reading before you attempt to root.
most of the common reasons to root have been eliminated with the infuse on att. so the common recommendation is not to root unless you plan on also doing Rom.

if you have the right file explorer, you can already see the file system.
but you can't change anything.
rooting will allow you to make the changes.

rooting will give you root permissions. meaning, the simple things that you can't do now, but not the high tech things that most can't do anyhow.

you know it, so picture this.
rooting does not give the ability to write windows code. but it does allow you to edit the registry. its those secret little nuances.
if you want to install non market apps (prior to the infuse) you needed to have root permission. if you want to delete the pre installed att apps, you need root permission. if you want to over/under clock the cpu, you need to root. changing the font size, root. deleting (on older phones, adding) ring tones, root.
little stuff like that.


as to any advantage.
i will repeat myself. most root advantages are silly or have been resolved with the infuse on att. its no longer necessary. unless...
anyone rooting an infuse should only be interested in also adding a custom Rom. the rest is pointless.

ok, so I rooted my infuse....got my unlock code but haven't unlocked the phone yet...can I unroot the phone and still be able to unlock the phone ?
and if I update to gingerbread before unlock will I be able to unlock after the update, or should I unlock first then do the update ?