Nothing, but nothing, can take the place of a good teacher. Especially a good music teacher, like the ones who helped turn my daughter into the amazing piano player that she is. They're worth every penny.
That said, music lessons can get expensive, and they're not always easy to work into your schedule. For example, I recently acquired a guitar, but I've yet to find the time or spare cash to take lessons.
I do, however, have an iPad. And with Howcast's new Guitar Lessons app, I'm getting professional instruction in basic guitar--on my schedule, whenever I can find a free 10-15 minutes. All for just $1.99.
There are other guitar-school apps available for iPad, but so far I'm finding everything I need in this one. It's basically a collection of 140-plus tutorial videos, all hosted by affable instructor Ivan Max. (They're all streamed, too, so you'll need an Internet connection.)
The videos are sorted into 12 categories. In Getting Started, Max shows you things like the parts of a guitar, holding a guitar properly, holding a pick, using a capo, and even what to look for when buying a new or used guitar (both acoustic and electric).
From there you can work your way through Stringing, Tuning, Open Chords, Practicing, and so on. The app cleverly tracks your progress, checking off lessons as you go so you can see at-a-glance which ones you've already completed. Plus, you can add any lesson to a favorites list for easy review later. There's even a search option, a nice touch.
Bottom line: If you want to learn the basics of playing guitar, Guitar Lessons is a convenient and inexpensive solution. It's no substitute for a live teacher, but it's a fine first step for novices.