What are “stops”, f/4 is referred to as a stop. It allows 2x the light than f/5.6, which is twice f/8…confusing right?
You can memorize the series of full stops: ƒ/1 ƒ/1.4 ƒ/2 ƒ/2.8 ƒ/4 ƒ/5.6 ƒ/8 ƒ/11 ƒ/16 ƒ/22 ƒ/32 ƒ/45 ƒ/64
Or find a chart like this:
Some cameras allow changes to the aperture in a variety of increments, starting from full stop to one-third stop. The Depth of Field (DOF) changes as you change the aperture, the bigger the aperture the shallower DOF (more Bokeh, or blur); the smaller the aperture the DoF gets wider.
Enough for now, but you should have a basic understanding of the f Stops.
Thanks for reading, keep on shooting, and, as always I look forward to your continued support.