system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: When tearing some types of paper like newsprint or napkins, why does it tear really jagged in one direction, but in a perfectly straight line in the opposite direction?
gpt
It has to do with the grain of the paper! Lots of paper follows the pattern of the wood it came off of, even if it’s so fine you can barely tell. So just like you chop on the grain, you tear on it as well to get a neat tear. If you tear against it, there’s no grooves for it to follow and it’ll come out more jagged and uneven.