Visu and Dylan told me that something is not a glitch, which made me think, what are and what not are glitches? If any mods could respond to this, that'd be gratefully appreciated.

a glitch is when you do something that is not intended in a game

ok..

There's a strat that i know but i dont know if its considered a glitch

I would say that glitches refer to using bugs (usually due to roblox mechanics) to your advantage. Something like player stacking isn’t a glitch as it’s a normal mechanic in the roblox engine, which can be used to speed up specific sections. However, frog jumping or wall clipping would be glitches since they aren’t intended on roblox whatsoever.

Ok, Good to know.