as a general rule -using a strong password
1 that is not shared with any of your other online accounts is your best defense against someone gaining access to your accounts. Also, not allowing your browser to store your passwords is another precaution that can help prevent this from happening. You can use a secure password manager like
KeePassX to genrate and manage your passwords.
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1RANDOM , mixed case alphanumeric with special characters is best. Password length is dependent on the application and website but the longer the better. you should at least mix the case and add numbers like this: JKoT9KVMR3dM.
Obviously cutting and pasting this as your password is not a good idea