Guitar/Slide Guitar
From Wikibooks, the open-content textbooks collection
A slide is a metal/glass/ceramic tube which fits over a finger (most commonly the ring finger or little finger, but any will work). If you wish to experiment with slide guitar, but do not have a slide, objects ranging from lighters and glass bottles to sections of metal pipe and batteries can work just as well, and in some cases provide entertainment and stage presence to a performance. Do not press the string down. The slide rests on the string, not enough to give fret buzz, but enough to stop the string buzzing against the slide. Some players will lightly deaden the string behind the slide with a trailing finger to stop any unwanted vibrations.
Practice getting a crisp note without sliding first. Because the slide rests on the strings, the slide playing a single note should be directly above the fret, not behind it as with the fingers. Usually the slide guitarist keeps the slide moving backwards and forwards slightly at all times.
A common technique found in slide guitar is playing fingerstyle as opposed to the use of a pick or plectrum. The benefits of fingerstyle playing includes the ability to more easily pick the desired strings, while using the other fingers to dampen the other strings from undesired vibration.
Slide guitar is often played in open chord tunings, Open G and Open D being the most common, but playing slide in standard tuning can add a new dimension to your playing.

