Rhythm and Rhythms

To learn to play in time you should really have a metronome. If you do not have one already I would advise that you should obtain one or a similar device (a drum machine for example) as soon as possible and incorporate it into your practice regime.
Metronomes are a device (either mechanical or digital) used for sounding beats per measure at a user definable tempo.
Now there is a better way to practice. New mark-my-time for music digital metronome monitors practice time at the touch of a button! It has never been easier or more fun to monitor practice time. The innovative mark my time for music digital metronome is a bookmark, digital timer and metronome all in one. With a simple touch of a button, students can record their own practice time.

http://www.mark-my-time.com
1. Programmable countdown timer tells students when
practice time is over.
2. Cumulative timer stores time to track multiple
practice sessions.
3. All-digital metronome features rich, traditional
tick-tock sound.
4. Flashing indicators show flashing beat.
5. Integrated clip conveniently attaches to music or
stand.
6. A440 tuning note.
7. 0-4 to 4-4- adjustable rhythm settings with accent
note.
8. Tempo range from 40-210 bpm
Metronomes are great when practicing to ensure that you keep a standard tempo throughout the piece of music. Wikipedia offers great history and uses of the metronome:

http://www.enwikipedia.org
When you practice jazz, you'll find James Wurbel giving jazz tips to rhythm success in his Jazz 101 Dvd and his use of the metronome to stay on beat:

http://www.hearandplay.com/441295/jazz

http://www.LadyDpiano.com