Sometime it happens in few cases that you are sharing a common pc and an user account with others. It may happen that you want few of your data to keep away the reach of other users.
use the below code with some modification(where specified) to lock your folder:
Now, place the above file dir_lock.sh on the same directory which you want to lock.
now type(in terminal):
1. $ cd <path to directory where your dir_lock.sh file exists>
2. $ chmod 500 dir_lock.sh
3. $ ./dir_lock.sh
from next time use $ ./dir_lock.sh to lock and unlock your directory.