If you enter 1 in a cell and then format it as a date , you get a different date in a Google sheet (12/31/1899 0:00:00), from the same action in Excel (1/1/1900 0:00)Is this an error ?  This is relevant to Historical or Sci-fi time travel Authors who use spreadsheets to create their plots and switch from Excel to Sheets and set them in the 1st 60 days of the 20th century.Programmers who rely on 0 or 1 in a date returning the same text result.That is all I can think of for now.   
Why does the same value produce different outputs when formatted as a date in Excel compared to Google Sheets?
google spreadsheets;microsoft excel