1. Passwords:

The most common passwords of vulnerable users are '123456' and 'password', according to a survey by security firm ImmuniWeb. Experts recommend 4 basic requirements for a strong password - an uppercase letter, a symbol, a numeral, and a minimum of 10 characters. Having a unique password for different accounts ensures hackers don't get easy access. Password management applications like Dashlane and Password Boss can help keep passwords locked down, security firm Norton says