Why we need installation

LaTeX can be run from the command line with a text editor and properly installed programs, however, I recommend using a LaTeX environment. This will simplify matters and also provide a development environment with useful properties such as syntax highlighting, compiling macros, etc.

When you have chosen your particular environment, type the following code and attempt to compile it.

\documentclass{article}
\begin{document}
This is my first \LaTeX document!  
\begin{equation}
     a^2+b^2=c^2
\end{equation}
I can write equations!
\end{document}