system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are some books (mostly reference and educational books) printed with two columns of text, as opposed to novels with one column?
gpt
Reference and educational books tend to have smaller type than novels. Smaller type means more words per line and it is harder to make sure you don't skip a line while you are reading. 

Also, information in textbooks and references tends to be much more dense than in novels. If you miss a word in a novel, you can usually figure it out based on context. If you miss a word in a reference text, it can be a much bigger problem.