I don't want to bore non-techies with this one, but I do want you to think about your passwords for just a few minutes.
The first thing is this: even if your password isn't something obvious like "password" or "obo", then hackers don't have to guess them. There is free, readily available software out there to do brute-force password hacking. So they can fire it up, go out for a cup of coffee, do the groceries, have a good night out and come back to find your password ready and waiting for them.
The second thing is this: the longer your password is, the longer it takes to crack.
The third thing is this: the more types of characters you use, the longer it takes to crack.
Let me give you a for instance: if I choose the password "obo", a brute-force cracker will take an average of 0.02 seconds to crack. So, "immediately". If I choose a slightly longer password, like "obnoxio", that will take two and a quarter hours. Much better, but still not really secure. However, if I simply change the password to include numbers and special characters, e.g. "Obnox1o$", it will take 210 years to crack.
And "Obnox1o$ Cl0wn" could take 154,640,721,434,000 years to crack using brute force.
So, put a bit of effort in, mix it up a little and make it just a little bit longer. Because it's worth it.
More info here.