Since your login name, which also is usually the prefix of your email address, is known to the world, it is only your password that protect your account. As such, you must protect your password that protect your account. As such, you must protect your password and keep it secret like your bank PIN numbers. You must know how to choose passwords. There are strong passwords and weak passwords.
Weak passwords are easy to guess.
Never choose names, places, items, initials or anything that can be easily associated with you. Examples of weak passwords are the name of your wife or children, your birthday, etc. Also, never choose common words. Passwords are case sensitive so you can combine small letters and capital letters to make them strong. Deliberate misspelling is also a good technique.