I often hear "Hakka", aren't they locals? Are you here as a guest?

No, Hakka is a Han ethnic group with distinctive characteristics. It is also one of the Han ethnic groups with the widest distribution range and the most far-reaching influence in the world. They live in some areas of Jiangxi, Sichuan, Guangxi, Hunan, Taiwan, Hainan, and Fujian, including Meizhou, Heyuan, and Huiyang counties in Guangdong, and are distributed in more than 120 counties. They lived in the Yellow River Basin for generations. In the late Western Jin Dynasty (early 4th century) and the late Tang Dynasty (late 9th century), a large number of people moved south due to wars. After the fall of the Southern Song Dynasty in the 1270s, they moved to Jiangxi, Fujian, Guangdong and other places. They call themselves "Hakka" or "Laijin" to distinguish themselves from the locals.