The LaTeX wikibooks says this:
This PDF was generated by the LaTeX typesetting software. The LaTeX source code is included as an attachment (source.7z.txt) in this PDF file. To extract the source from the PDF file, we recommend the use of http://www.pdflabs.com/tools/pdftk-the-pdf-toolkit/ utility or clicking the paper clip attachment symbol on the lower left of your PDF Viewer, selecting Save Attachment. After extracting it from the PDF file you have to rename it to source.7z. To uncompress the resulting archive we recommend the use of http://www.7-zip.org/. The LaTeX source itself was generated by a program written by Dirk Hünniger, which is freely available under an open source license from http://de.wikibooks.org/wiki/Benutzer:Dirk_Huenniger/wb2pdf. This distribution also contains a configured version of the pdflatex compiler with all necessary packages and fonts needed to compile the LaTeX source included in this PDF file.
But when I compile the source code I get an error in the terminal that says that pdflatex isn't installed. Then what is the configured version of pdflatex?