Commercial "pop" music has had one positive impact on the guitar: it has "democratized" the instrument making the instrument, and the music, accessable to almost anyone as a portable "everyman's" instrument.
But, in the process, "pop" has had a very negative impact as well -- it has given rise to many social myths: that the guitar is "easy"; that it doesn't require knowing music; that different kinds of guitars are limited to specific kinds of music; that it certainly doesn't require the kind of studious effort, long practice time and, and interminable scale studies of the piano (which many people remember less than fondly from their childhood); and that it is a musical instrument for non-musicians. None of these are true.
The guitar is a polyphonic (2 or more melodic lines) instrument which can be played either for accompaniment or solo music.
As an accompaniment instrument you can play the guitar while singing along, either by yourself or with others. You can strum chords or you can play "broken" chords using a variety of arpeggios.
As a solo instrument you can play arrangements and pieces that comprise melody, harmony, and bass simultaneously.
Best of all, you can combine the two into some really nifty arrangements allowing you to sing and play and insert an instrumental bridge.
It is a fully self-contained instrument and in all of this the guitar has much in common with keyboard instruments.
But, the guitar is also one of the two most complex instruments, the other being the organ, and so there is no such thing as 10 Easy Lessons -- at least, not if you want to play well and enjoy all the guitar has to offer.
There is also no such thing as "folk guitar", "jazz guitar", "classical guitar" etc. The guitar, like any other instrument, plays music -- any and all kinds -- and the techniques available are all equally applicable to all forms and styles of music.
There are different kinds of guitars: the nylon strung "classical" and "flamenco" guitars; the steel strung "acoustic" (which is a flat top to which the strings either attach directly to the bridge or to a tailpiece), or "arch-top" (sometimes called a "jazz" guitar), or "resonator" (also referred to as a "dobro"); and the hard-body electric. Each has its own voice, but none are limited nor specific to any particular style or genre.
And, again regardless of what kind of music you eventually want to play, the fundamentals are the same.
The best approach to learning the guitar is to determine to learn to play the instrument rather than to play certain music on the instrument -- determine to be as versatile in the music you play as the instrument is. The first Lessons are always the most difficult and some students will drop as a result. Other students will get to about the early intermediate level, think they can now play "well", and then drop the course of study only to find later on that they don't play as well as they thought they did.
But -- if you are willing to work at this and to learn as much as you can then you will be able to play anything and everything.
Which is not to say that learning the guitar is all about scale studies and long practice times. Equating the instrument to a specific methodology is a mistake.
Yes, scales are important to know, but just going up and down scales is a waste of effort.
Yes, you do have to practice, but it is amazing what you can get accomplished in just 10 minutes. 3 10 minute sessions in the course of the day gets you half an hour of practice time and you can choose when to do those short sessions so that they will fit with your busy schedule.
There is a whole world of wonderful music available to you with the guitar -- wanna learn to play it? Let's get started...... 
