What makes a tabby cat different than other cats??

This is regarding a Pinterest post (below) I saw the other day that showed many different tabby markings (pin-stripe, freckled/speckled, agouti, clouded, etc). If a tabby can have all of these markings, how can I tell if a cat is a tabby cat? Or is 'tabby' an umbrella term of sorts?

https://preview.redd.it/ainjly50wmce1.jpg?width=736&format=pjpg&auto=webp&s=6917fa9c57cbfd4daf75e02046c5bd0cf0893396