Question: From what I see [here](http://en.wikipedia.org/wiki/Kerning), it seems kerning is just rearranging the space between letters. However, the comments [here](http://area51.stackexchange.com/proposals/1924/graphic-design/1929#1929) lead me to believe there's more to the story. Is kerning really that simple? Is the only purpose of it to look nicer or is there some practical reasoning for it?

Answer: 
Yes, that is essentially it. [From Wikipedia](http://en.wikipedia.org/wiki/Kerning):

> 
> In typography, kerning (less commonly mortising) is the process of adjusting the spacing between characters in a proportional font, usually to achieve a visually pleasing result. In a well kerned font, the two-dimensional blank spaces between each pair of characters all have similar area. The related term kern denotes a part of a type letter that overhangs the edge of the type block.
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the point of making it looking nicer is the only point, but it can be *very* important for a clean-looking typeface. The Wikipedia page shows how massive the difference can be:

![alt text](https://i.stack.imgur.com/fVg91.png)
The main reason to pay close attention to kerning is for readability. Visual appeal is also very important. Another reason is that a properly kerned word will typically take up less horizontal space than an unkerned word, therefore allowing larger type sizes (this is useful for book cover design and poster design). 

For more information, check out this previous article by me: [What the Heck is Kerning? The Fundamentals of Good Typography](http://www.hensher.ca/what-the-heck-is-kerning "What the Heck is Kerning?")