Definition
SKU stands for "Stock Keeping Unit", meaning the items that are effectively in your inventory.
At VTEX, SKUs are hierarchically under Product.
SKUs and Specifications
A Specification is a SKU characteristic ascertaining to the difference of that SKU from other SKUs linked to the same product.
Further on this track, we'll go into more details on how to add SKU's Specifications. For now, it's important to know that SKUs differ by their Specifications.
Examples
Fashion
Let's say for example that your shop sells T-shirt.
The T-shirts represent your products, however, your customers will in fact purchase the various types of T-shirts that your store offers.
A customer will not just shop for a "T-shirt", in fact, the physical product sent to the customer’s address will be a "red medium size T-shirt", for example.
T-shirt size and color are, in this case, product Specifications. The size specification values available are "S", "M", and "L". The color specification values are "blue", "red", and "yellow".
Home Appliances
We will now analyze a home appliances store use case. One of the most common departments in such a store is related to "kitchen utensils", with one of the categories of this department being "microwave ovens".
There are, of course, several types of microwave ovens.
You may choose a Microwave with an Integrated Control Panel, either with a 127V or a 220V voltage option. We can safely say that the voltage options is, in this case, the specification that differ the SKUs of the "Microwave with an Integrated Control Panel" product.
Home Décor
Lastly, we’ll look at a store specialized in home décor.
The idea is the same: let’s say that you are buying an orthopedic mattress.
You will need to access the "Mattress" department, followed by the "Orthopedic" category.
Imagine that you choose a product called "Continental Sleep mattress", but it comes in different sizes.
The SKUs in this case are "Continental Sleep Mattress - Twin size", "Continental Sleep Mattress - Queen size", "Continental Sleep Mattress - King size", while the product is the "Continental Sleep Mattress".