1st String (High): D
2nd String: B
3rd String: G
4th String: D
5th String: A
6th String (Low): E
These strings are typically made of steel, bronze, or nylon, and come in a variety of thicknesses and tensions to accommodate different playing styles and preferences. The gauges (thicknesses) of these strings are typically:
.009" - D (1st string)
.012" - B (2nd string)
.016" - G (3rd string)
.023" - D (4th string)
.030" - A (5th string)
.036" - E (6th string)