TITLE: In (relatively) simple words: What is an inverse limit?
QUESTION [245 upvotes]: I am a set theorist in my orientation, and while I did take a few courses that brushed upon categorical and algebraic constructions, one has always eluded me.
The inverse limit. I tried to ask one of the guys in my office, and despite a very shady explanation he ended up muttering that "you usually take an already known construction."
The Wikipedia article presents two approaches, the algebraic and the categorical. While the categorical is extremely vague for me, the algebraic one is too general and the intuition remains hidden underneath the text in a place I cannot find it.
Since I am not too familiar with categories, the explanation most people would try to give me which is categorical in nature seems to confuse me - as I keep asking this question over and over every now and then.
Could anyone explain to me in non-categorical terms what is the idea behind an inverse limit? (I am roughly familiar with its friend "direct limit", if that helps)
(While editing, I can say that the answers given so far are very interesting, and I have read them thoroughly, although I need to give it quite some thinking before I can comment on all of them right now.)

REPLY [10 votes]: I like the picture of a cocone from http://arxiv.org/abs/math/0306223:

They describe it through a story about people sending emails to each other.
And then:

A cocone which is universal is a colimit. ―http://ncatlab.org/nlab/show/cocone


Added:

Colimits glue. Limits cut. ―Adam Hughes