The Explore command in Google Docs, Sheets and Slides allows you to research information without leaving your file. You will receive instant suggestions based on the content of your sheet, and can view related topics at any time. 

As well as a feature that allows you to ask plain English questions about your data, the Explorer option in Google Sheets now includes formatting suggestions, to help you present your data in the best way for your audience. In addition, you can ask the Explorer option to create charts based on your data. 

To explore the data in a sheet:

If the Explore button shows in grey, this means that Google has no insights to offer on your data. Try selecting specific data in the sheet to view insights on that data.