ani ni siya, in technical words, there are couple types of downloading/accessing files over network, this are the most common

1) HTTP
2) FTP
3) Peer-to-Peer

kanang mag download sa browser or mga downloader, and usually accessing it using http:// or https:// protocol is called HTTP downloading/accessing

FTP can be accessed by couple ways thru an FTP client (e.g Filezilla,FireFTP) or you can directly access it thru browser usually it starts with ftp:// protocol or thru terminal console/telnet, however when you upload you need an FTP client or a terminal console/telnet

i recommend FireFTP cross platform as long as you have firefox, Filezilla is good but it limited support on some OS, like Mac OSX tiger... i used FireFTP daily....

Peer-to-Peer, commonly used on torrent and filesharing application like Kazaa,Limewire,Napster and Bearshare, you download file from its source where the file is shared, however torrent is slightly different because everytime you download you also uploading a file bits (seeding) to other computer that is dowloading that file... thats why it is important to check if there are lot of seeders before downloading... considering it has low leeches...