A general source of information on Linux is the Linux Documentation Project. There
you will find the HOWTOs and pointers to other very valuable information on
parts of a GNU/Linux system.
If you want to buy a CD set to install Debian GNU/Linux system from CD-ROM you
should look at the CD
vendors page. There you get a list of addresses which sell Debian
GNU/Linux on CD-ROMs. The list is sorted by country so you shouldn't have a
problem to find a vendor near you.
If you live outside of the USA and you want to download Debian packages, you
can also use one of many mirrors which reside outside the USA. A list of
countries and mirrors can be found at the Debian FTP server
website.
United States laws place restrictions on the export of defense articles, which, unfortunately, includes some types of cryptographic software. PGP and ssh, among others, fall into this category. It is legal however, to import such software into the US.
To prevent anyone from taking unnecessary legal risks, some Debian packages are
available from a server outside the US which serves the various cryptographic
programs: Debian non-US
Server.
This text is taken from the README.non-US file, which you can find on any Debian FTP archive mirror. It also contains a list of mirrors of the non-US server.
In Linux you have various special files in /dev. These files are called devices files. In the Unix world accessing hardware is different. There you have a special file which actually runs a driver which in turn accesses the hardware. The device file is an interface to the actual system component. Files under /dev also behave differently than ordinary files. Below are the most important device files listed.
fd0 1. Floppy Drive
fd1 2. Floppy Drive
hda IDE Harddisk / CD-ROM on the first IDE port (Master)
hdb IDE Harddisk / CD-ROM on the first IDE port (Slave)
hdc IDE Harddisk / CD-ROM on the second IDE port (Master)
hdd IDE Harddisk / CD-ROM on the second IDE port (Slave)
hda1 1. partition of the first IDE harddisk
hdd15 15. partition of the fourth IDE harddisk
sda SCSI Harddisk with lowest SCSI ID (e.g. 0)
sdb SCSI Harddisk with next higher SCSI ID (e.g. 1)
sdc SCSI Harddisk with next higher SCSI ID (e.g. 2)
sda1 1. partition of the first SCSI harddisk
sdd10 10. partition of the fourth SCSI harddisk
sr0 SCSI CD-ROM with the lowest SCSI ID
sr1 SCSI CD-ROM with the next higher SCSI ID
ttyS0 Serial port 0, COM1 under DOS
ttyS1 Serial port 1, COM2 under DOS
psaux PS/2 mouse device
gpmdata Pseudo device, repeater data from GPM (mouse) daemon
cdrom Symbolic link to the CD-ROM drive
mouse Symbolic link to the mouse device file
null everything pointed to this device will disappear
zero one can endlessly read zeros out of this device