Ground bass- a bass part that recurs over and over whilst the melody voice over it change and vary continuously. It was developed in England in the 16th century and was used extensively in the baroque period. Bass line never Changes.
http://www.youtube.com/watch?v=hOA-2hl1Vbc


Continuo- the part that is played by a harpsichord, usually a bass line and a harmony part in one.

 Figured bass- this is a bass line with a figured bass telling the player where to harmonise with figures.

 Concerto Grosso- of music developed in the 18th century involving a small group of instruments and a large group of instruments. these two groups are usually contrasted or sometimes played together.A concerto grosso has several parts that differ in speed and character. There are usually three movements; the first is fast, the second is slow, and the last is fast.

http://www.youtube.com/watch?v=2kaNnZFosm8

String Quartet- a string quartet is a chamber music ensemble that has part of it the first and second violins, a viola and a cello. They became popular in the late 1700's.