Ports are kind of like apt-get but work very diffrently. There is a ports tree you enter into (/usr/loca/ports I belive under FreeBSD) and then find the application you want from within the sub catogories and then type make install clean to have it installed. It then processes through makefiles and something else (can't remember what it is off the top of my head...) and it looks for dependencies, downloads source, builds it, creates a package, and then installs the package. Thats the basics of the whole deal, look at the whitepapers and makefiles for more.