LaTeX is not a word processor, it's a typesetting language. When writing a LaTeX document, instead of telling the program exactly how you want each part of the text to be formatted, you mark the text as being "abstract", or "section", or "bibliography", and the LaTeX compiler formats it appropriately. Later if you want, say, all of your examples to be offset from the text with a box around them, you re-define what an "example" should look like, rather than reformat everything.

LaTeX can also create for you ---automatically, and without much effort on your part--- tables of contents, tables of figures, indices, footnotes, and bibliographies.

This is particularly valuable for larger projects. The Phys 312 textbook you may have used earlier in your physics coursework here at CSUC, for example, is a collection of LaTeX files pulled together by one "master file". Many books are also written in LaTeX: see "Numerical Methods for Physics" by Alejandro Garcia, as one of many examples.