Simplify Formulas with Named Ranges
Perhaps you knew that you could name cells, but did you also know that you can name ranges? This is super-handy if you find your self referencing the same range over and over again in your spreadsheets.
To name a range, select the range, click "Define Name" and give it a name. You can now use this name to reference the range in your formulas.
Range names have the same restrictions as cell names (it must be unique, start with a letter or underscore, and cannot contain spaces).