There are two main visa options available to skilled and highly skilled workers who wish to work in the UK.
The format of your visa will depend on your nationality. The UK is moving to a digital by default immigration system with a long term plan to phase out physical visas. The first group affected by this change will be EEA and Swiss Nationals.
If you are an EEA or Swiss nationals applying for a work visa you will not receive a physical entry clearance or visa. Instead you will have a digital visa record that is accessible by the UK Border Force and which you can share with your employer and / or landlord. You can find information on the digital visa on the Home Office website.
Non-EEA nationals will continue to receive physical visas for the near future. When applying for a visa outside the UK you will need to submit your passport, which will be returned with a 30 day entry clearance. On arrival in the UK a Biometric Residence Permit (BRP) will be sent to the address you chose on your application, normally a local Post Office. This will normally be available for collection within 10 days of your arrival in the UK.
If you are applying for a visa within the UK your new BRP will be issued by courier to your home. You can find information about BRPs on the Home Office website.