Google Docs made collaborating on files so much easier, as it lets several people edit the same document concurrently, without having to worry about version numbers or consolidating changes. However, there are times when you can't use the service and have to rely on locally saved files. This is often the case when interacting with clients or people unfamiliar with collaborative software, who send their edits without activating Revision mode. For these cases, it's always handy to have the computer compare the two versions and highlight changes for you. Although Microsoft Word has been capable of doing this for ages, Google just made it possible on its software.
The newly added feature lets you compare two documents directly from the web interface. To do so, you need to open the first document in Docs, then click on Tools -> Compare Documents and fetch the version to compare it against. This will create a new file highlighting changes as suggested edits. To make it easier to recognize, you'll be asked who the differences should be attributed to, which will make the changes appear as if they were made by a particular user directly in Docs, as shown below.
In terms of availability, the feature will begin rolling out starting today but may take until early July for all users to see it. Lastly, Google hasn't shared whether its mobile app will also be able to compare documents easily, which would also simplify proofreading on the go.
- G Suite Updates Blog