Excel processes the range (A1:A10) by converting it into an array in memory. This array is what Excel works with to calculate the sum. The distinction is subtle but important: while the range is the ...
Press Ctrl+; to insert the current date. Press Ctrl+Shift+; to insert the current time. Press Ctrl+; > Space > Ctrl+Shift+; to insert the current date and time together in the same cell.