user name and password

No its the worst strategy to stay safe. In fact its a hacker's delight and a big security risk. Sometimes people working with you could get know your password (by simply looking at the keyboard). Soon, that person will have access to all your email-id, and maybe even password locked word files, zip files etc. (you will lose a lot, just don't try this). Also, always use alpha numeric 8+ character long passwords as they can't be easily hacked.

No its not, ya i agree it gets difficult to remeber them as we have so many sites n accounts, but still is advised that we shud keep different passwords ,or user id.also we shud not keep the same password for long. Its difficult but its must to be safe on the net which is full of phishers n scammers n spamers. Thanks.