At the heart of virtually all of today's clogging steps is a simple two-tap movement called the double toe. You execute a double toe by quickly kicking forward from the knee, then allowing the leg to fall back naturally. Because you don't lift the foot very far off the floor, this kick forward and back makes two quick sounds: a tap as the ball of the foot brushes foward and another tap as it brushes back. The double toe is then usually followed by stepping onto the ball of that foot, which also makes a sound. Together, all of that makes a "double toe step." The first two sounds of the "double toe step" fall on the upbeat ("and a"), and the step falls on the downbeat.
The basic step (The Clog) consists of a double toe step, a rock or brief transfer of weight to the other foot, then a step back again. (In tap dancing terminology, a clog would be shuffle step ball change.) With the counts, the notation of a basic clog (also called a "basic") looks like this:
DTS Rk S (Double toe step, rock, step)
L R L (Left, right, left)
&a1 & 2
The "basic" clog is the fundamental building block of almost all the other steps. Other than the Double toe, Step and Rock, there are very few fundamental foot movements in clogging: the Heel, Toe, Brush, and Drag complete the list. There are dozens of well-known clog steps today (and hundreds of obscure ones!), but practically all of them grew out of some variation of these few components.