Getting a handle on some Latin basics
It's difficult these days (maybe even impossible) to turn on a music station and not hear a Latin clave pattern. Dig deeper and you'll find clave rhythms or some derivative just about everywhere: the clave 'clap' of hip-hop, the bossa bass drum in Rosanna, the venerable Bo Diddly beat … it's all clave. (As for demystifying this versatile rhythm, there are so many options, variations and subtleties that we may have to settle for merely documenting a few of them.)
Culturally Specific
The clave rhythm proper is the aforementioned Bo Diddly beat, and it's traditionally played with claves, which are short, thick, wooden ideophones (i.e. fat sticks). The clave rhythm comes in a few varieties and serves as a framework and marker for a Latin tune. In 4/4, the pattern spans two bars and has two distinct forms. In the 3:2 form, the first bar contains three 'pulses' and the second bar contains two. Reverse it and you have the 2:3 form. Here is the Son clave:
More of a Good Thing
There are variations on the basic clave form, and variations on the variations. The two most common are the rumba and the bossa nova. Again, each can be played in a 3:2 or 2:3 forms
Clave in Modern Times
The 'half clave' is ubiquitous in popular music. It's simple and reliable, and adds quite a bit of rhythmic interest. It's also easy to relate to, which is perhaps why it's used so often in hip-hop and top 40 tunes.
A simple modification can completely change the character of the clave. Compare the standard bossa nova rhythm to Toto's Rosanna. Just one small change gives us something totally new.
And I think that should be enough for now.
(* pronounced claw-vay)