There is no limit to the number of cells you can create. Cells to which you assign one or more offers in Campaign are called target cells. A target cell is a distinct group of homogeneous audience members. For example, cells can be created for high-value customers, customers who prefer to shop on the web, accounts with on-time payments, customers who opt to receive email communications, or loyal repeat buyers. Each cell or segment you create can be treated differently, with different offers or contact channels, or tracked differently, for comparison in performance reporting.

Cells containing IDs qualified to receive an offer but that are excluded from receiving the offer for analysis purposes, are called control cells. In Campaign, controls are always hold-out controls.