Nikkei is derived from the term in Japanese, used to refer to Japanese people who emigrated from Japan and their descendants. Emigration refers to permanent settlers, excluding transient Japanese abroad. These groups were historically differentiated by the terms "issei" (first-generation "nikkeijin"), "nisei" (second-generation "nikkeijin"), "sansei" (third-generation "nikkeijin"), and "yonsei" (fourth-generation "nikkeijin"). The term Nikkeijin may or may not apply to those Japanese who still hold Japanese citizenship. Usages of the term may depend on perspective. For example, the Japanese government defines them according to (foreign) citizenship and the ability to provide proof of Japanese lineage up to the third generation—legally the fourth generation has no legal standing in Japan that is any different from another "foreigner." On the other hand, in the US or other places where Nikkeijin have developed their own communities and identities, first-generation Japanese immigrants tend to be included; citizenship is less relevant and a commitment to the local community becomes more important.