Linux at my work

if you have multiple sessions in a signle terminal, and you want to ALT-TAB btw them from keyboard - ANS : SHIFT-ARROW-KEY in which ever direction, based in the session you want to select.

1. I had a situation where there was a variable by name "production.variable" being used in a java file, but i wanted to know where it is being used apart from this java file, i have multiple folders under which there were many java files and XML files, now how to find which of these files use production.variable"

ANS : grep production.variable -R *
[OR]
grep 'some strings with spaces' -R *