Double-Stop: The act of playing two notes simultaneously - two separate strings are "stopped" by the fingers.
A technique drawn from many types of bluegrass music, double-stopping features the most intense dynamic of all. Strictly finger-style, we'll be combining a couple different techniques and highlighting some very major-scale sounding country rhythms.
Keeping your index and middle fingers "glued" together for these exercises is imperative. It will ensure the highest level of accuracy when playing the double-stops which are exclusively played on adjacent strings.
Double-Stop Exercise 1 (A Blues): Keep a close eye on the M's, I's and T's beneath the tablature, as they're essential to making this riff have its bluegrass/country attack. It's very simplistic scale-wise, but it's bound to throw you for a loop technique-wise!
Double-Stop Exercise 2 (F Major): Starting out with some bending as practiced in the last section, this one quickly throws in some double-stop action that'll be sure to twist your fingers.
M: Middle Finger
I: Index Finger
T: Thumb