Unless you want a thief or snoop rummaging around in your phone or tablet, you need to set up your gadget's lock screen. Fortunately, most newer gadgets have you do this by default, but if you bypassed this, or have an older gadget that didn't require it, here are the instructions for turning it on.
The lock screen traditionally requires you to enter a four-digit code or a full password to use your gadget. Most people opt for the four-digit code, even though it isn't that secure. It's well-known that many people choose obvious codes like "0000," "1111," "1234" or "0852" (swiping up the center keys), but even harder pass codes won't keep out a determined hacker for long.
The reason most people don't go for a full password, however, is that a long password is a pain to type every time you want to use your phone, which could be dozens of times a day. That's why gadget makers have added more convenient medium-security alternatives like facial unlock, fingerprint scanning or, in Android's case, drawing a pattern.
For most people, drawing a pattern is the preferred solution. Facial unlock isn't actually that secure and, outside of Apple's iPhone and the newest Samsung Galaxy phones, fingerprint recognition is a little spotty. A pattern is fast to enter, easy for our brains to remember, and with nine possible pattern points, there are too many combinations for a thief to try.
At least, that was the theory.