TeX has been developed between 1977 and 1986 by Donald E. Instead of typing in a document showing why using dvi insted of pdf final layout the document is typed as a simple text file. To get an idea of what we are talking about, lets run through a short example.
For Windows MiKTeX is a good choice. This is my first section! Even referencing other sections is very easy. When it is finished execute the same command again. Open it in your favorite PDF-viewer like i. Adobe Reader and you will see something similar to the screenshot on the right.
When you write a document you should concentrate on its content insted of its layout. This is hard when working in WYSIWYG environment. When inserting a figure there you might move it to different positions until you get the look you like. So you can concentrate on what matters: The content.