The shrimp dumpling named by Wikipedia as the most common type of Cantonese gaau ji is har gow.
Cantonese gaau ji are a regional style related to jiaozi. They are generally smaller than northern-style jiaozi and use thinner, often translucent wrappers suited to steaming. Har gow is the classic shrimp-filled version, typically made with a delicate starch-based wrapper that becomes semi-transparent in the steamer.
Har gow is a staple of Cantonese dim sum. Its filling commonly centers on shrimp, with seasonings and ingredients such as bamboo shoots, scallions, sesame oil, or cooked pork fat varying by recipe. The wrapper must be thin enough to look translucent but sturdy enough to hold the juicy filling.
Har gow is often served alongside siu mai, another famous dim sum dumpling, but the two are not the same: har gow is characteristically shrimp-filled and translucent, while siu mai usually has an open-topped wrapper and a different filling and appearance. Zongzi are rice-filled parcels, and baozi are filled steamed buns, so neither is the Cantonese gaau ji type described here.