Google Sheets (formerly known as Google Spreadsheets) is a browser based, collaborative spread sheet program that runs as a cloud service. It is part of Google Docs office suite which in turn is part of the larger package Google Drive .
Also Microsoft Excel's xls and xlsx files can be imported to Google's spread sheet program.
Other Google Sheets type of services include Microsoft Excel Online.
It is not advisable to upload personal ID data or sensitive information to Google services.
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