Computer security - protecting information on a computer is always current. It applies not only to computer security when you're online, and physical protection of the local machine from unauthorized access. Working in the office where the computer contains confidential proprietary information that we are required to saprolite. At home too, sometimes, have to do it. It all depends on the household situation.
. The simplest protection is to put a password on login. See how to password protect your user account in Windows XP. Instructions for Windows 7 is not much different from the previous one, but will look into it - will move into a lesson about the account password in Windows 7. So, we read the lessons and learn to set a password for entrance.
And reliably insure - created file to reset the password and saved it on a flash drive. However, it happens that you forget your user password, and the file is not available or lost. And someone just didn't know about the file of password change.
Often this happens in the office. After a long absence from work safely forgotten the password and cannot log in. In Runet circulates many descriptions of various technologies reset various passwords.