Sanjeev,
you got the zip... expanded it. and double-clicked the startup.bat.
The full answer of course can be found at the Tomcat home page
Jakarta Tomcat... but the short answer is:
Windoze: at a command prompt:
To permanently set this in Windoze 2k and above:
Open the Properties sheet for My Computer:
Right-click on My Computer > Properties > Advanced Tab > Environment Variables
Do the same as above but add a new System Variable with the name of JAVA_HOME and a value as shown above.
Then edit the PATH System variable as shown above to include the bin directory of your
Java SDK.
UNIX is a variant of this but since the variants set paths differently I'll cover Bash:
In your home directory edit the .bash_profile file to include something like:
Of course all this is moot if you do not have the Java SDK installed. This is not the same as the JRE! Get the full Software Development Kit (SDK) for Java from the Sun website. v1.3x and 1.4x are fine. Tomcat 4.1.12 is 1.4 ready. The LE download of Tomcat is optimized for 1.4 by the way.
Hope this helps,
Tim