The UAE's visa policy is very flexible. It's a great country to live in and work in, with many jobs available for foreigners. The visa you need depends on the type of work you are doing and your length of stay.
Residence visa is for those who want to stay in the UAE longer than 90 days. It's a visa that allows you to work in the country and live there.
Employment visa is for those who want to work in the UAE for a period of time. It's a visa that allows you to work in the country, but not live there.
You can work for a company in the UAE on a residence visa, and you can work for a company in the UAE on an employment visa.
If you want to work for a company in the UAE on a residence visa, you can stay for up to three months. If you want to work for a company in the UAE on an employment visa, you can stay for up to six months.