.uk and .co.uk are both run by Nominet, the UK registry.
Quirky stuff like .co.uk / .org.uk / .sch.uk 2nd level domains partly come around from .uk being the worlds first CCTLD outside the US (and as other parts of this thread say, .us isn't that popular a CCTLD).
Everything was new and different people tried different hierarchy and structures to 2LD and 3LD's. .co.uk is also far from unique, I know this is common in many other places (UK/NZ/IN/ZA/KR/MX).
The UK now allows directy foo.uk registrations as well, but many people still have SLD's registered and will continue to do so.
Quirky stuff like .co.uk / .org.uk / .sch.uk 2nd level domains partly come around from .uk being the worlds first CCTLD outside the US (and as other parts of this thread say, .us isn't that popular a CCTLD).
Everything was new and different people tried different hierarchy and structures to 2LD and 3LD's. .co.uk is also far from unique, I know this is common in many other places (UK/NZ/IN/ZA/KR/MX).
The UK now allows directy foo.uk registrations as well, but many people still have SLD's registered and will continue to do so.