We have plenty of "what is X for?" questions.
- What is 'Ubuntu Unity' (for the Desktop)?
- What is a virtual terminal for?
- What are shells?
- What is a segmentation fault?
- What is Ubuntu Soyuz?
- What is edge.launchpad.net and how does it work?
- What is Ubuntu One?
- What is "Steam" and how does it work?
- What is zeitgeist used for?
- What is the loopback device and how do I use it?
- What is Ubuntu Touch (Ubuntu for Phones)
So you're right that construing questions like What is apt and what are its uses? and What is apparmor? as automatically too broad is a radical approach.
What is apt and what are its uses? is misleadingly named. It's actually asking "What are the uses for all the apt- commands?" That's not all that broad. I don't think this is one of the most valuable questions on the site, but it's not too broad.
To respond to the idea that this question is lazy: We have plenty of questions that are lazy in the sense that they ask for information that is extensively provided elsewhere, such that no answer is likely to describe anything that was not previously presented elsewhere on the Internet or in documentation. Like How do I reset a lost administrative password? and How can I repair grub? (How to get Ubuntu back after installing Windows?).
To respond to the idea that this is somehow like a list question: A list question is bad because it can have an unlimited number of answers, with no way to objectively evaluate one compared to another. In contrast, this is asking for the discrete list of utilities that comprise APT and what they do. This question is also not requesting "one utility per answer," and it wouldn't make sense if it did, since a good answer will synthesize information about the different utilities, explaining how they relate to one another.
While poorly named, What is apt and what are its uses? is valuable because a good answer would teach novices about all the utilities that comprise APT, dispel the myth that APT consists only of apt-get, and explain how the utilities perform different functions, showing how they can be used separately or together.
As for What is apparmor?: I believe most users of Ubuntu are poorly familiar with AppArmor. A question with an excellent answer that summarizes its purpose accessibly is a very good thing. Besides that we have many other questions asking what particular parts of Ubuntu are, we know this question has answers that aren't "a whole book" or anything close. So this is not too broad under the FAQ either. That this question and answer are highly upvoted should be considered evidence that they are, in fact, valuable to Ubuntu users and the Ask Ubuntu sub-community more specifically.
Some of the answers that are mostly verbatim quotations from other documentation don't speak well for themselves or the questions they're answering. So Jorge Castro is right that What is apt and what are its uses? looks bad right now. But that question can be answered well, by giving shorter descriptions of each apt- command than are present in their manual pages (while still more accessible descriptions than whatis would give).
What is apt and what are its uses? was posted just a week ago. If a long while passes and nobody posts a good answer (as I've defined it), then it might be reasonable to close it as too broad... though it would be better to simply leave it alone (it has an upvoted answer, after all, and it's not really off-topic). But I doubt that; I would strongly consider posting what I consider a good answer there, if it weren't for my concern that the question is just going to be closed (and then possibly deleted).
###The FAQ says "You should only ask practical, answerable questions based on actual problems that you face"!
Right, and both these questions fit well within that.
Stack Exchange started as just Stack Overflow. Among the general population, the word "problem" has strong connotations of "a bad thing that needs to be fixed or more bad things will happen." Among programmers (and other problem solvers within a technical, quantitative tradition--mathematicians, engineers, etc.), a problem is a situation that admits to a solution.
This more general sense of "problem" is well-known and commonly-used by the general population, too. If someone says, "I'm so glad to be able to work on this interesting problem," most people are not confused.
That is how we should interpret "problems" in the FAQ. Historically, it only makes sense that this is the intended meaning. But also, we'd have to close a significant percentage of all open questions (probably on most or all Stack Exchange sites) if we insisted on the narrower interpretation.
Needing help understanding how a significant part of a system on which one relies is a problem in both senses of the term (i.e., this might even fit within the more restrictive sense of "problem"), and that describes the impetus behind both of the questions brought up here.
We don't interpret "actual, practical problems" to refer only to specific, imminent bad events. We never have, SO doesn't, and as far as I know, no SE site does. What is the philosophy behind Unity's name is considered a fine question.
The APT question--which is apparently more controversial, perhaps because the AppArmor question has one of the best answers ever posted on Ask Ubuntu--comes down to the practical need to know how a central piece of Ubuntu works and what its parts do.
No one opposes comparable questions about Unity, like What's the right terminology for Unity's UI elements? and What are Unity's keyboard and mouse shortcuts?. If we should really only ask for help with a specific task, those would be considered bad, too.
Most of the questions in the list that begins my answer only represent "problems" in this wider sense, too. That's why I listed them. This addendum to my answer serves to clarify and explicate my claim that "practical problems" really means a real situation, where a question can be answered or solved, and you can check if the answer is right.
Related: Questions "just for curiosity"
