When Ripple is used (or Auto-Ripple enabled), any time you select and then remove a segment of audio from the timeline, everything that followed after that point will be shifted in time to an earlier time position by the amount of time corresponding to the duration of the removed material. When Ripple is
not enabled, removing a portion of audio will leave a gap in the timeline.
Alternatively, if you have Auto-Ripple enabled and
insert some audio at the cursor position in the timeline, everything that follows after that point will be shifted to a later time to accommodate the inserted material. If Auto-Ripple was not enabled, the inserted material would simply overwrite whatever occupied the time following the insertion point.
While it's off-topic, it can be useful to have Auto-Cross-fade enabled when adding or removing audio clips in the timeline. This way any clips which become "butted up" to each other will automatically have your Default cross-fade applied to them. (Set up and save your Default Cross-fade values in the Fade Editor Tab.)
Pyramix is not the only DAW which uses the term "Ripple" in this way: Pro Tools, Adobe Premier, Reaper, etc. Here's a link to a Craig Anderton article on the subject:
https://craiganderton.org/understanding-ripple-editing/