Like its predecessor, Windows 10 allows you to sync your settings across compatible devices (PC and mobile) on which you are signed in with your Microsoft account. By enabling this option you can automatically apply most if not all of your custom settings and preferences to all of your Windows 10 devices. This may include your current desktop theme (layout, color theme...), browser settings (bookmarks and password), accessibility options, language settings and much more.
It should be noted that when you first install Windows 10, you will be asked if you want to sync your settings or not. You have skipped this section? No worries, here's how to sync your settings:
Sign-in to your Windows session (with your Microsoft account). Click on Start > Settings > Account > Sync your settings. Toggle Sync settings on and choose the settings you want to sync: