What is special about ".com.sg" vs ".sg" and similar domains?

Question

Domain name market

For example, take the domains aabb.sg and aabb.com.sg
What is special about com.sg? Why do such domains exist for many countries, because there is just "sg"?

Answer 1

you chose the wrong example. cc domains are subject to the most stringent requirements by their coordinator.
.sg - for individuals and non-commercial sites
.com.sg - commercial only.
when registering, you must specify the company ID that is issued by the government. If the ID does not match the company name, you can say goodbye to the domain. At best, they will block "until clarification", at worst, they will delete it. Money is not returned.
But this is so, a little exaggerated for brevity and clarity of understanding.
And all the rest, as answered above, is a matter of taste and availability