The Coleman slide, or any longboard slide for that matter, is an important skill needed for going down hill where you might need to stop short (for example, riding on a hill where cars drive).
This instructable covers the Coleman slide which is considered the best first slide by many boarders. After learning this slide, you can move on to many other slides like pendulums, standing slides, and others.
Sub Note: I do not have any pictures of myself sliding, so Instead I have used a picture of the inventor of the Coleman slide, Cliff Coleman.
Image Source: http://www.geocities.com/sk8sanjose/coleman.jpg