Sideloading (is supposed to) mean just transferring files between local devices, as in, you aren’t uploading or downloading them, you are going sideways. E.g you download a song to your pc, then sideload it to your mp3 player.
That’s also where it comes to installing phone apps, as you transfer the app file to the phone yourself. Being “outside” or “going around” the official method just happens to be another way to interpret the meaning of “side” in the word.
English is my third language, it’s hard to remember which parts of it belong to a fourth one and shouldn’t be translated (because “en masse” is literally French for “in mass”)
When one community goes in mass to affect the votes in another. E.g someone is doing a poll/vote intended to be private or limited to a certain group/community, and you link that to from somewhere else with the hope, or sometimes direct instructions to go vote on it in a certain way.
That’s why reddit has cross-posts and the np (no participation, disables voting in the linked content) subdomain that try to keep the votes separated.
Disk rot usually happens when air gets in contact with the reflective coating and oxidises it. With CD’s, it’s actually the top side you need to be worried about, as it’s right there under a thin lacquer coating. Any ding to that can expose the layer or just literally chip off a chunk of data.
At least on DVD’s it’s sandwiched inside the disk, so usually the only reason is a manufacturing error, and not really something the user can cause.