Hei Cha (黑茶) is a category of post-fermented tea.
When translated into English, Hei Cha literally means ‘black tea’, although most people in Western cultures would refer to Hei Cha as a ‘dark tea’.
This category of tea includes Hunan hei cha, Sichuan Hei Cha, and so forth.
Although pu’er tea is sometimes classified as a type of hei cha, it is a large enough category that it’s usually thought of as being in it’s own category.