And I'd also opt for a Kleimheist or Autoblock over the classic Prusik.
Not sure if I think this was a good selection of essential climbing knots and the presentation was odd. For instance, I'd present the Prusik in an abseiling context. The article mentions using a Prusik to ascend their rope when they've fallen off an overhang, and I have yet to see that. What I see routinely is someone using a Prusik of some sort as a backup when abseiling.
But don't go climbing outdoors if you don't have someone that is experienced to go along with you. Take a course or several. It is possible to learn on your own, but it is a high-risk activity to figure these things out as you go on your own. Accidents, even fatal ones, happen to people that know what they are doing.
I carry a couple of prussik loops primarily for abseil backup, but have also used it to recover from a fall off an overhang when seconding. The leader was far enough away they couldn't hear me asking to be lowered. I also couldn't reach the rock so had to ascend the rope. Prussik gets the job done.
If anyone is curious, I recommend reading https://www.andy-kirkpatrick.com/blog/view/rappel-knots-1 (it has helpful illustrations on why the EDK doesn't catch)
And I'd also opt for a Kleimheist or Autoblock over the classic Prusik.
Not sure if I think this was a good selection of essential climbing knots and the presentation was odd. For instance, I'd present the Prusik in an abseiling context. The article mentions using a Prusik to ascend their rope when they've fallen off an overhang, and I have yet to see that. What I see routinely is someone using a Prusik of some sort as a backup when abseiling.
If all of this sparked the curiosity of someone I recommend VDiffClimbing for further information https://www.vdiffclimbing.com/abseil/
But don't go climbing outdoors if you don't have someone that is experienced to go along with you. Take a course or several. It is possible to learn on your own, but it is a high-risk activity to figure these things out as you go on your own. Accidents, even fatal ones, happen to people that know what they are doing.