The UK government is providing a number of immigration, naturalization, work permit, visa options which allows people from other countries to come into UK to Work, Live, Visit, and Study. Before coming into UK make sure you understand your legal situation in UK. Depending on your nationality you might need a visa to enter into UK. Though UK provides many option to enter into UK they have got very tough immigration laws. Before travelling to UK make sure you have got the right visa and travelling documents otherwise you will be refused entry into UK.
UK Home Office who is responsible for immigration services has got three main categories for issuing visa and immigration service.
European Economic Area Citizens: Do not need entry clearance to enter the UK. The European Economic Area (EEA) includes all EU countries plus Swiss, Norway, Liechtenstein and Iceland nationals also fall under this category.
Non-Visa Nationals: Only require an entry certificate when going to the UK to work or to settle. This category primarily consists of Commonwealth citizens but not all the Commonwealth countries are included into this category.
Visa Nationals: Need a visa to enter the UK for any reason.
Please note that UK immigration rules are subject to change from time to time so please make sure to get the latest immigration rules and regulations from the home office.