“Autofill” feature in Google Chrome browser saves what you type in form fields. The next time you fill out a form that you've completed in the past, what you've previously entered pops up below each field. Use your mouse or Tab on the keyboard to select the text you want to use. The autofill text is stored on your computer as part of your browser profile.  You can always go to the Clear browsing data menu to delete saved form data from your computer or turn the feature off entirely in the Options menu.

Source:→ Chrome Blog