Typing equations on the computer can very quickly become very messy, U= IR is okay, but “the integral from -pi to pi of sin(x) dx” is very difficult to read. Therefore LaTeX is used.

$$\int_{-\pi}^{\pi}\sin(x)dx$$

LaTeX is enabled by typing double dollar signs, and closed by double dollar signs . Subsequently commands are used in between the dollar signs. In the example this is

Some common commands are summarized in this table

There are many more commands, and you can quickly find them by using google, “LaTeX command theta” for instance.