Here's how you can set up a picture password for login in Windows 8.1.
1. Move your mouse to the lower right corner of your screen.
2. Click on Settings.
3. Click on Change PC Settings.
4. Click on Accounts.
5. Click on Sign-in Options.
6. Click the Add button under Picture Password.
7. Follow the instructions to set up your Picture Password.
Not only does using a picture password make signing in faster, it also makes your PC feel more “yours” because you get to use whatever photo you want. And, a picture password can actually be more secure than a regular password because there are an almost infinite number of combinations of things you could tap, circle, or draw a line across in any given photo.More at Windows