Connect is a connection type that allows you to import or export an entire sheet. For example, from your active spreadsheet connect to another spreadsheet, select a sheet inside this spreadsheet and import all its data into a new sheet inside your active spreadsheet. Or, connect to another spreadsheet and export an entire sheet of your active spreadsheet to the connected spreadsheet. This will create a new sheet inside the connected spreadsheet and insert the data from your selected sheet inside your active spreadsheet.
You can also apply a filter or a query to only import or export specific data instead of the entire sheet.
Step by step tutorial:
Select Import or Export.
Search for your spreadsheet to connect to.
Select the sheet inside the connected spreadsheet you want to import into your active spreadsheet.
Click Connect to create the connection and import the sheet from the other spreadsheet into your active spreadsheet.