Guitar Tuning 101
There are many ways to tune your guitar, depending on what style and sound you are going for. Here are a few common tunings.
Standard tuning is the tuning that most guitars are originally set up to be played in. In this tuning, your strings are tuned to E-A-D-G-B-e from low to high. Normal chord voicings and finger positions are used in this tuning, and this is the tuning that most people use for the majority of their playing.
In the days of classic rock, E flat tuning became popular. This tuning takes standard tuning and moves every string back one half step, giving you Eb-Ab-Db-Gb-Bb-eb. Tuning a guitar in E flat reduces string tension which allows you to play bends more easily and effectively than in standard tuning. Additionally, this tuning lowers all the notes in standard chord progressions, meaning singers do not have to strain their voices as much to hit high notes.
Drop D Tuning
Drop D tuning is common in heavy metal and rock an roll. This tuning is similar to standard tuning, except that the low E string is tuned to a D. This allows you to play power chords by simply covering the bottom 3 strings on a given fret with one finger. Many cool riffs over the ages have been written in drop D tuning.
Open D and open E tuning
In open D tuning, the strings are tuned so that when you strum all the open strings, you hear a D major chord. To achieve this, you tune the strings as follows: D-A-D-F#-A-D. Open E tuning is much the same, except that the open strings play an E major chord (E-B-E-G#-B-E). These open tunings are often used in the blues genre, and are especially useful when playing the slide guitar.