1. Kingdom: The broadest category, like animals or plants.

2. Phylum: A group of closely related classes, like chordates (animals with a backbone).

3. Class: A group of closely related orders, like mammals or birds.

4. Order: A group of closely related families, like primates or carnivores.

5. Family: A group of closely related genera, like the cat family (Felidae).

6. Genus: A group of closely related species, like the genus *Panthera*, which includes lions, tigers, leopards, and jaguars.

7. Species: The most specific level of classification, like *Panthera leo* (lion).

This system, called the Linnaean taxonomy, is still the basis for how we classify organisms today.