A product line can be thought of as a brand. In other words, it is a collection of products grouped together and sold by a company. Companies will utilize different product lines for different purposes. For example, a company might sell different product lines in different regions or at different price points.
A product mix or assortment is the grouping of all product lines sold by a company. These can be understood according to four dimensions:
- Width – The number of product lines a company sells.
- Length – The total number of products a company sells.
- Depth – The measure of variations among all products a company sells.
A product extension is the method a company uses when new products are added to an existing product line or brand (think of all of the variations on Coke that Coca-Cola has implemented). This strategy helps bring variety to a product line and attracts new customers.
A product filling is the extension of the number of products to meet demand. This is not the addition of new products (like a product extension is), but rather the increase in the amount of a particular product sold in order to adjust for demand. This could be based on sales trends (a particular product selling better or worse) or seasonal offerings.