Blues and Classic Rock

• There's a tradition amongst blues players of using heavy gauge strings, the theory being that the thicker string allows for a greater intensity of vibration, conveying more sound detail, and as a result, a more detailed and evocative tone. If you're a new player, gradually increase gauges one at a time, to give your guitar and your fingers a chance to adjust. Some popular brands are D'Addario, Fender and Gibson. Pure Nickel strings are a little more expensive, but produce a warmer, mellower tone than their plated counterparts.
  
  

Metal

• The guitars used to play heavy metal and hard rock are unique, and often include locking headstock nuts, floating tremolos and powerful active pickups. There are dedicated Metal string sets available too, most commonly in "hybrid" format. these include light gauge strings for the upper three strings, for the execution of high-speed solos, and massive heavy gauge bass strings, for creating that fat, chunky rhythm sound. The heavier low-end strings are also well-suited to de-tuning, a very common technique in metal. Ernie Ball and Rotosound both produce hybrid sets, and heavy metal legends such as Zakk Wylde and Dave Mustaine endorse signature sets by Dunlop and GHS.
  
  

Jazz

• Jazz guitar, whether electric or acoustic, has a distinctively clean, mellow sound. A specific string choice has a great deal to do with this. "Flat-wound" strings are manufactured in a way that emulates some of the early string producers. The core is laid flat on a bench, and the outer winding is rolled around it. This produces a smooth surface, which is often smoothed out further with precision grinding. Flat-wound strings are less in demand, and as a result can be harder to find. Fender and D'Addario produce some popular sets in a variety of gauges.
  
  

Acoustic

• Acoustic strings are available in steel or nylon versions. It's important to determine which variety your guitar needs, as fitting the wrong ones can damage the tuning hardware and neck. Nylon strings tie to the bridge, where steel ones are anchored by cylindrical pegs. Bronze plating is commonly used on steel acoustic strings to mellow the tone and protect it from corrosion. This is not done with electric strings as it would interfere with the magnetic signal detected by the pickups. Nylon strings are a replacement for the animal gut used up until the 1940s. Martin and Elixir manufacture highly regarded steel acoustic strings, and D'Addario and Augustine are considered the best of the Nylon versions.