Okay let me begin with telling you that I aint good at “networking” and probably just have a day or two knowledge of it .. but i got a good idea of it now i think!
Okay lets start with ports , they are like open doors to you computers .. there ports ranging from 0-65535 i think so if any of them is open someone can gain acess to your computer depending on the rights of the user set to that port .. what a firewall does is close all ports unless you specify a particular port to be open!
ports are not physical so stop wondering where are the 65535 holes in your comp! 
no most services have default ports like
- http port:80
- ftp port:21
- telnet port:23
- ssh port:25
these are the default ports but other ports can be used to set them up .. someone can access these services from your computer using these ports and with certain access rights like edit read write and other attributes set to the user .. to certain sections of your hard disk .. what a hacker does is open a port on your comp ( with a trojan mostly perl scripts with cgi extensions ..google it!! ) and then set the rights to edit and del on whole of your comp and all he has to do is insert a nice little virus ( mostly a batch file {.bat if you didn’t know} if a infinite loop calling most programs and deleting a few key process like … na i aint gonna say that .. search for it.. ) .. okay so got till this point clearly?
well now okay so how to you search for open ports .. ? well try using something called NMAP. it’s awesome for searching for open ports and once you find open ports just telnet them or ftp them depending on the protocol set to that port .. and if you are lucky it will set to a anonymous account ( that is anybody without a user and password can enter it lucky you!! ) ..
more on this later … need to pack and get back to the campus for now ..
Sala Kahle till then!! bbye
P.S : try using a ftp client like Filezilla for ftp access!!
