Google is getting ready to change the sign-in prompt for your accounts sometime this month. The change seems to relate only to the UI, since essentially the function won't change.
Although redesign is not important, any change to the web page of major web sites is remarkable, as many users who will meet the different login page for the first time will wonder if they are a real page or if someone tries to steal their password.
Google allegedly redesigned the login page without changing its functionality. The last major changes to this page were made from 2013 to 2015.
In the new login form you must first enter your username (usually the email), then click on sign in and give your password.
Below you see the Google sign-in page that will be released for everyone in June:
As you notice the Google logo looks different, the text field, username and password have borders around them, and the whole form is centered on the screen.
Below is the old login form so you can compare them: