Trying out Linux has always been considered a challenging and dangerous proposition. Faced with repartitioning their hard drive or finding a "spare" PC to use, most users see Linux as a lot of work, with an uncertain payoff. But what if I told you there was a way to try Linux without installing, partitioning, or making changes to your hard drive? Thanks to the work of some dedicated Linux developers, all this and more are possible today. The solution? Live CD Linux.

"Live CD Linux" is a new breed of Linux distribution. It's a complete solution for using Linux on a computer without touching the hard drive. Unlike traditional Linux, live CD distributions run directly from a CD-ROM. You simply insert the live CD and boot your system. Everything then runs from the CDoperating system and applications. Although this isn't a perfect solution for everyone, it's a great way to try Linux without making potentially hazardous changes to your system.

Live Distros can also be stored on other bootable media a CD-ROM (Live CD), DVD (Live DVD), USB Flash Drive, Key drive, among others.

If you want to test drive Linux to see if it works with your hardware or simply if it suits your style, Live CDs are very handy.

You can almost do all the things you can do in a desktop Linux environment with a Linux Live CD. You can, for example, surf the web, email, chat, open or create an office document, print or read/write to a floppy or USB pen drive. Of course, this is just a small list of things a Live CD can do.

LiveCD distributions of Linux are several years old, but the number of such distributions has multiplied several times in the last year or two. There are dozens, if not hundreds, of LiveCD distributions available now; obviously, you'd be only interested in the most useful and popular ones. The most popular focus of LiveCDs is probably general-purpose office software bundles, particularly aimed at showing off Linux to new users. At the edges, however, other distributions aim at more specialised purposes, such as system clustering, rescue CDs, firewalls, or security tools. In many cases, the more specialised distributions are also smaller, since they leave off most general-audience tools. You can check out a detailed list of LiveCDs at http://en.wikipedia.org/wiki/List_of_LiveCDs

Here we take a look at a few of the popular Linux LiveCDs out there.

Knoppix
Knoppix is a bootable CD with a collection of GNU/Linux software, automatic hardware detection, and support for many graphics cards, sound cards, and other peripherals. Knoppix can be used as a Linux demo, educational CD, rescue system, or adapted and used as a platform for commercial software product demos. Due to on-the-fly decompression, the CD can have up to 2 GB of executable software installed on it. Knoopix was developed by Klaus Knopper.

Several factors contribute to the popularity of Knoppix: for example, it has extensive hardware detection capabilities that allow most systems to boot straight into a graphical environment. It also connects automatically to many types of networks and has many utilities for data recovery and system repairs (even for other operating systems, which means Knoopix can be used to fix up your primary Windows setup). It also includes popular software for desktop use (notably web browsers, OpenOffice.org, the GIMP).

Knoppix has a wide variety of free software but includes also proprietary software. More than 2600 software packages are included on the DVD edition and more than 1000 are included on the CD edition. Up to 9 gigabytes can be stored on the DVD in compressed form. When a program is used, it is decompressed into a RAM drive. The decompression is transparent and on-the-fly. At least 128MB of RAM is recommended in order to accommodate this RAM drive.

You can download Knoopix at http://www.knopper.net/

Puppy Linux
Puppy Linux is a very small, reliable, easy to use and fully featured LiveCD Linux distribution started by Barry Kauler. The entire operating system and all the applications run from RAM, making Puppy a very fast system, and allowing the boot medium to be removed after the operating system starts. Included are applications such as Mozilla Application Suite, AbiWord, Sodipodi, Gnumeric, OpenOffice.org (when using Chubby Puppy, an extended version of Puppy Linux) and Gxine/xine. The distribution is independently developed from scratch and is regularly updated and is well supported and documented. Like other LiveCDs, Puppy is considered useful for working on old computers, as an emergency rescue system, as a Linux demonstration system, or as a complete general purpose operating system.

Puppy Linux is 40 MB and can be downloaded from http://www.puppylinux.org/

Ubuntu
Ubuntu is a complete desktop Linux operating system, freely available with both community and professional support. The Ubuntu community is built on the ideas enshrined in the Ubuntu Manifesto: that software should be available free of charge, that software tools should be usable by people in their local language and despite any disabilities, and that people should have the freedom to customise and alter their software in whatever way they see fit. "Ubuntu" is an ancient African word, meaning "humanity to others". The Ubuntu distribution brings the spirit of Ubuntu to the software world.

Ubuntu includes more than 16,000 pieces of software, but the core desktop installation fits on a single CD which doubles as a LiveCD. Ubuntu covers every standard desktop application from word processing and spreadsheet applications to web server software and programming tools. It's also has what's probably the nicest and sleekest Linux interface out there.

Ubuntu is available for download at http://www.ubuntu.com/, but they will also send copies of Ubuntu to you if you request it at https://shipit.ubuntu.com/.

Of the Live CDs, Knoppix is definitely the easiest distribution to get up and running. With excellent hardware support and a wide array of included software, Knoppix is hard to beat, but Puppy Linux comes pretty close with the features it offers in a tiny package. Ubuntu is, however, the nicest Linux desktop environment to work with.

Although you can't buy a LiveCD at the local CD vendors, it's not too hard to get a LiveCD. The easiest method requires a CD burner and a broadband Internet connection. Just download an ISO image of the CD and burn it with programs such as Nero or Easy CD. If you're on dial-up, you can still try downloading the smallest LiveCDs over a period of a few years. Seriously though, Puppy Linux is only 40 MB, which means even on dial-up, you can download it within 5-6 hours.

Or, you can request an Ubuntu LiveCD at https://shipit.ubuntu.com/. Ubuntu is this new very-user-friendly Linux distribution that's enjoying a lot of popularity recently. The Ubuntu community is trying to spread the use of the distribution a lot recently and is shipping copies of the Ubuntu to anyone who request them. It takes some time for the CDs to reach here, but it's worth it.

After you have the CD, make sure that your system is configured to boot from CD. This is the default behaviour for many newer systems, but you may have to go into BIOS and change your boot sequence. Check your PC or motherboard manual or the manufacturer's web site for instructions.

With ease of use, hardware compatibility, and an installation-free approach, LiveCD Linux has removed many of the obstacles facing users considering a switch to Linux. If you're getting tired of all the problems Windows has got to offer, it's never been easier to find out if Linux is really the answer.

Acknowledgement: Thanks to Ross Hunter, David Mertz, James LaRue, Harish Pillay and Wikipedia for their research on the topic. For Wikipedia's more detailed entry on Live Distros, head over to http://en.wikipedia. Org/wiki/LiveDistro