A password which consists of combination of Special Characters, Numbers, Upper and Lower Case letters is more difficult to crack then a simple string of numbers or alphabets. Most people set 123456, password, 12345678, qwerty, abc123 etc. as their password which makes a hacker’s job a hell of a lot easier.
Take a look at the image to see how much time it takes a hacker’s computer to randomly guess your password. The 1st column describes your password’s length and other describes the time to crack it.