At the beginning of an Excel spreadsheet formula, the function of the word '=SUM' is

The '=SUM' function in Excel is used to add together a range of numbers. It is one of the most commonly used functions and can take multiple arguments, allowing you to sum individual values, cell references, ranges, or a combination of all three.

Details on the Function

1. Basic Usage: The simplest way to use the SUM function is to provide a range of cells, such as =SUM(A1:A10), which will add all the values from cells A1 to A10.

2. Multiple Ranges: You can also add multiple ranges by separating them with commas, like =SUM(A1:A10, C1:C10), which will sum all values in both ranges.

3. Adding Individual Values: You can sum individual numbers directly in the formula, for instance, =SUM(1, 2, 3, 4), which will return 10.

4. Efficiency: Using the SUM function instead of manually adding numbers is much more efficient, especially in large datasets where summing manually would be impractical.

In summary, '=SUM' is essential for performing addition operations quickly and efficiently within Excel spreadsheets, making it a fundamental tool for data analysis and calculation.