Hi guys,
I have just started exploring linux on Debian OS. Till now I was using windows Operating System. Now I came across with u know lots of shell commands like chmod, chown, chgrp, mount, umount etc.

Still I don't have much knowledge about the scope of linux/unix and areas where I should focus on. I am a J2EE programmer and I was just curious in exploring java technologies on it. But I think now I should go more into that beside just using java on it.

Can you guys give me some direction, some specific areas where I should concentrate more on. Any tutorial or stuff on it would be higly appreciated.

Thanks in advance

- Naseem

It's very difficult to make blanket judgments about what general knowledge you need to run Linux. Think in terms of what you do on Windows, then set out to do the same thing on Linux. It won't be the same procedure, but sometimes you'll be able to figure it out on your own, and sometimes you can ask specific questions here about how to accomplish what you need.

Maybe start off learning to use vim if you don't already know it. There is a nifty "vimtutor" that ships with it.

I find it easiest to learn things about Linux by finding a project to work on.

Wether it's setting up a CMS website using LAMP (Linux, Apache, Mysql, PHP)
Or configuring a Mail server
Or a DNS or DHCP Server
Current projects include Asterisk and Hylafax.

Without a project to focus my direction I kind of flounder and 'don't know what to learn next'
With a project in hand you pickup what you need to get the project completed and working.

My suggestion is to do some readig and find some interesting projects to work on, the learning will come as you work on things.

Given your profession and Farslayer's advise I'd suggest to dive into the task of installing Java on your Debian system. You'll find you'll need to learn how the bash shell works. There's an command overview here and good tutorials (known as HOWTO's) on various subjects on the Linux Documentation Project website here