The Apache license is what is termed a "permissive" license. This means, essentially, that the license imposes very few restrictions on the code's users versus, for example, reciprocally styled licenses. So few restrictions, in fact, that the open source may be embedded in proprietary software.

Permissive licenses are employed, typically, where project owners want to maximize either or the distribution. They are also preferred by commercial organizations because it imposes few restriction usages, as discussed above. For more on the usage see the section concerning platform licensing here.

As for the Apache vs MIT question, it comes down to ancillary licensing factors. Both licenses will render the asset permissively licensed, but the Apache license additionally speaks to actual copyright and - in version 2.0 - also includes an explicit patent grant. Here's a good discussion on StackOverflow on the subject.

My (OSS agnostic) answer tends to fall along two lines:

• The GPL is great if your focus is making money because it affords you the most control over the product, within the "limits" of it being an open source and free product.
• The Apache license is great if you're concerned with ubiquity above revenue - you want to get the software out there as widely as possible vs. control it's distribution.

Also, there are considerations of community & foundation involvement. If you want to get involved with the Apache Foundation, or Eclipse, and so on. Each of those communities has requirements for licensing choices.

Part of that is the brand value you'll get from a licensing choice. For the most part, this is about signaling to your community what your intentions are: if it's a permissive license (Apache or MIT, here), you're saying something slightly different than if it's a GPL license. I often tell closed source companies who're looking to get market zing from open sourcing that going with the GPL makes their effort seem more real and committed. That said, this kind of marketing side-effect of open sourcing seems to matter (and come up) less and less now-a-days than it did 1-2 years ago.