ASIN = Amazon Standard Identification Number
An alphanumerically unique identifier, consisting of 10 characters. Every product that is created at Amazon gets an ASIN, the SKU within Amazon. In addition, as a seller, you can specify your own internal SKU. Other sellers can do the same, but you will not see this information from other sellers.
Amazon product page urls look like this:
The ASIN of an Amazon Eco Dot is B07PHPXHQS. The URL then becomes: