The United Arab Emirates consists of seven emirates (Arabic: إمارات ʾimārāt; singular: إمارة ʾimārah), which were historically known as the Trucial States.
[1] All emirates are founding members of the union, apart from Ras Al Khaima which joined two months after the rest.
There is almost always full freedom of movement between the different emirates of the UAE (an example of an exception is that during the COVID-19 pandemic, for instance, there were limitations of movement between the various emirates).
[2]