What are these High frequency Artifacts from or cause by?

In Clock,timer, pulse generator circuits

There is ripple on the High state

There is High frequencies between the pulses

 

Here is the o-scope pictures of the waveforms

 

What are these High frequency Artifacts from or cause by?

In Clock,timer, pulse generator circuits

There is ripple on the High state

There is High frequencies between the pulses

If at the start, then transients or transient response. If in steady-state, then interference, bad design.

 

Are there interferences? what kind to cause this?

what about the ripple riding on the logic High State?

 

Take a look at the pictures and what do you guys think it is?