how to know history of commands in shell

HI all its very easy
for some shell its
> history n where n is the number of last executed commands . like to know the last 10 commands just [...]

how to know which bash version u r using

based on ur default shell , suppose ur shell id /bin/sh , then
> /bin/sh –version OR if its bash , then
>/bin/bash –version

how to know the linux version

Its very easy , just type this in ur terminal
> lsb_release -a

How to search a word in all files in linux

This is very easy and can be done by using grep command .
> grep -R “word to search” * > log.txt
Well only grep -R “word to search” is enough .It will display the result in terminal. If you are using > sign , then it will be written in that log file.

How to find any files in dir and its subdirectory

its very simple
> find -name “*.html” | grep “index”
Here to find index.html in the current directory and subdirectory .. .use find and grep to find the file .

how to unpack the jar file in linux

The command is very easy .
> jar xf yourjar.jar
This will unpack the jar files and make folders like com and jar bean .jar files

how to zip file in linux

suppose there is folder name “backup” containing subfolders and files then,
> zip -r backup.zip backup

how to find difference between two revisions in svn

shell > svn diff -r filename
It will show +++++ where the changes had been done.

how to take backup myqsl dump in linux

shell> mysqldump -u root -p –all-databases > db_dump.sql

how to download the contents in linux

wget (http://downloadURL.com)