Chromebooks run Google's Chrome OS (operating system) and are designed to work best when connected to the internet. Most applications, documents and files are stored in the cloud
If you browse as a Guest, you'll be able to use Google Chrome to access the web.
If you login with your personal Google / Gmail account, you'll be able to access your Google apps including Docs, YouTube, Keep, Gmail, Chrome, Calendar, Maps, Drive, Sheets, Slides, Photos, Camera, Calculator and more.
Signing in with your own account allows you to save your files to your personal Google drive.
You may also be able to access your virtual desktops using a Chromebook
If browsing as Guest - Sign Out
Your files, cookies, website data, and browsing activity will be deleted from the Chromebook.
If you signed in with your Google / Gmail account - Remove the account from the Chromebook
On the sign-in screen, click the profile that you want to remove.
In the upper-right corner of the profile picture, click the Down arrow .
Click Remove this person.
In the box that appears, click Remove this user.
When you remove an account, it’s only removed from the Chromebook. The Google Account itself, including its data and settings, will still exist.