Another class of alternative tunings are called drop tunings, because the tuning drops down the lowest string. Dropping down the lowest string a whole tone results in the "drop-D" (or "dropped D") tuning. Its open-string notes DADGBE (from low to high) allow for a deep bass D note, which can be used in keys such as D major, d minor and G major. It simplifies the playing of simple fifths (powerchords). Many contemporary rock bands re-tune all strings down, making, for example, Drop-C or Drop-B tunings.

Learn the C chord. The first chord we will cover is a C chord—one of the most basic chords in music. Before we do, let's break down just what that means. A proper chord, whether played on a piano, a guitar, or sung by well-trained mice, is simply three or more notes sounded together. (Two notes is called a "diad," and while musically useful, is not a chord.) Chords can also contain far more than three notes, but that's well beyond the scope of this article. This is what a C chord looks like on the guitar:

Getting to grips with how chords are formed gives you a basic introduction to music theory and helps you understand the ways you can alter them to create more interesting sounds. All chords are built from certain notes in scales. The C major scale is the easiest, because it just runs C, D, E, F, G, A and B. These notes are numbered (usually using Roman numerals) in that order, from one (I) to seven (VII).
Jump up ^ "We know from literary sources that the five course guitar was immensely popular in Spain in the early seventeenth century and was also widely played in France and Italy...Yet almost all the surviving guitars were built in Italy...This apparent disparity between the documentary and instrumental evidence can be explained by the fact that, in general, only the more expensively made guitars have been kept as collectors' pieces. During the early seventeenth century the guitar was an instrument of the people of Spain, but was widely played by the Italian aristocracy." Tom and Mary Anne Evans. Guitars: From the Renaissance to Rock. Paddington Press Ltd, 1977, p. 24.
Some piezo-equipped guitars use a hexaphonic pickup. "Hex" is a prefix meaning six. A hexaphonic pickup produces a separate output for each string, usually from a discrete piezoelectric or magnetic pickup for each string. This arrangement lets on-board or external electronics process the strings individually for modeling or Musical Instrument Digital Interface (MIDI) conversion. Roland makes hexaphonic pickups for guitar and bass, and a line of guitar modeling and synthesis products. Line 6's hexaphonic-equipped Variax guitars use on-board electronics to model the sound after various vintage instruments, and vary pitch on individual strings.
Unlike many string instruments which use a bow to create a sound, guitars are played by plucking or strumming the strings on the instrument, which vibrate to create a sound. Chords are played when the guitarist holds their fingers down on more than one individual string to change its length, which in turn changes the frequency of the vibration created - in other words, it creates a different note. Performers often use guitar tabs, rather than sheet music, when learning music: this acts as a kind of 'map' to teach guitarists where to put their fingers on the strings.