Both Koreas use the Hangul script for official purposes, but there are lots of regional differences as words enter the language from other cultures in the South, while the North has remained relatively isolated. For example , there is no single word for "helicopter" in North Korea. And, the word for "octopus" in the North translates to "squid" in the South, but the South Korean word for "squid" means "octopus" in the North.