Work with cells using the Excel JavaScript API
The Excel JavaScript API doesn't have a "Cell" object or class. Instead, all Excel cells are Range objects. An individual cell in the Excel UI translates to a Range object with one cell in the Excel JavaScript API.
A Range object can also contain multiple, contiguous cells. Contiguous cells form an unbroken rectangle (including single rows or columns). To learn about working with cells that are not contiguous, see Work with discontiguous cells using the RangeAreas object.
For the complete list of properties and methods that the Range object supports, see Range Object (JavaScript API for Excel).
Work with discontiguous cells using the RangeAreas object
The RangeAreas object lets your add-in perform operations on multiple ranges at once. These ranges may be contiguous, but they don't have to be. RangeAreas are further discussed in the article Work with multiple ranges simultaneously in Excel add-ins.