These are bootable disks that can be used to boot up a
computer to one of many available Linux distributions
(operating systems) without making any permanent changes to
your computer. Reasons why you might want to do this
include:
to rescue files from a failing hard disk when you
cannot boot from the hard disk as you normally would
for greater security when carrying out banking or
credit card transactions on the Internet
to isolate problem areas in general computer
troubleshooting (if you cannot boot from the hard disk
but you can successfully boot from a live cd, it means
the problem lies with the hard disk or the operating
system (usually Windows) stored on the hard disk)
The number of available live cd/dvds is in the hundreds so
choosing one can take some time. The best starting point is
probably Distrowatch
and for more on the history of Linux try Wikipedia
For what it is worth the following is a list of the live
cd/dvds that I have found useful (the two things that I
generally look for in a Linux distribution are wireless
connectivity and multimedia playback)
As a general desktop operating system
Linux Mint 12
Super OS 11.04
Fusion Linux 14.1
Sabayon 7
openSUSE 12.1-1
Some distributions (distros) try to offer a much more
complete selection of (usually) multimedia applications,
some of these are
ArtistX 1.2
AV Linux 5.0.3
Dream Studio 11.10
Ultimate Edition 3.0.1
At the other extreme, some distros are specialised for
troubleshooting, data recovery and system rescue tasks, e.g.
RIP Linux 13.7
SystemRescueCD 2.5.0
DEFT 7
One of the characteristics of a live cd/dvd is the lack of
persistence, i.e. any changes you make while in a live
session, such as installing new codecs/applications,
downloading files or changing the desktop appearance are
lost as soon as the computer is rebooted. This can be both
an advantage and a disadvantage. The advantage is that each
time you boot to the live cd/dvd you are booting to the
original, pristine operating system environment, untouched
by any virus or malware files that you may have
inadvertently downloaded during a previous session. This
makes a Linux live cd/dvd a much more secure environment in
which to carry out online banking and credit card
transaction than a normal Windows desktop PC.
When selecting the best live cd/dvd to meet your individual
needs there are a few differences between Linux distros that
should be kept in mind:
Does wireless networking connectivity work out of the
box (several years ago it was not uncommon to have to
fiddle around to get things such as sound and wired
networking connectivity working. Now these things do
generally work out of the box but you can still come
across distros that lack wireless networking
connectivity).
Does multimedia playback work out of the box (e.g. is
the flash player plugin installed in the web browser).
Does the distro have a "copy to ram" option. The
significance of this option is that copying to ram frees
up the cd/dvd drive for use by discs other than the live
cd/dvd itself.
What user account does the live cd/dvd use for
automatic login. When working with Linux distros it is
good security practice NOT to login as the all powerful
root account. Most general purpose live cd/dvds will
automatically login as a non-root account. However there
are some distros that do automatically login using the
root account. To be sure what user account is being
used, open a terminal window and execute the command
"whoami". The output of this command should be something
other than "root".
Is it possible to install new codecs and/or
applications (packages) in ram during a live session.
Many modern distros allow this so you can, for example,
download and install the flashplayer plugin if it is not
already installed. These new codecs or applications will
be lost once the computer is rebooted.
What additional applications (packages) are available
to be downloaded and installed and what package
management system is used to do this. One of the most
significant differences between the various Linux
distros is the package manager that they use.
It is up to you to decide which of the above are important
to your needs. It is useful when making your decision to
know that various Linux distros do have the differences
listed above.
