What is a 'hard' Brexit?
Theresa May is expected to set out her vision of Britain's exit from the European Union on Tuesday.
May previously promised to invoke Article 50 of the Lisbon Treaty - the official mechanism to leave the European Union - by the end of March 2017, before a two-year period of negotiations follow.
But the main question being asked is what relationship Britain will have with the rest of the EU once the process ends, leading to the use of the terms "hard" and "soft" Brexit.
Here we look at what a "hard" or "soft" Brexit might look like.
Hard Brexit - favoured by Brexiteers
Give up full access to the single market
Have full access to border control and immigration
Make independent trade deals
Apply new rules within its own territory
Rely on the World Trade Organisation
Soft Brexit - favoured by Remain campaigners
Remain, as close as possible, to the existing arrangements
Britain's exports not subject to border checks
Accept "four freedoms" - movement of goods, services, capital and people
This will offer continued free access for EU nationals to live and work in the UK and membership of the European Economic Area
What countries use the 'hard' and 'soft' methods?
Despite not being EU members, Norway, Iceland and Liechtenstein are members of the European Economic Area.
This gives them full access to the single market, and in return, they have accepted the "four freedoms" and are subject to EU law.
Further to this, Switzerland has 120 separate bilateral agreements with the EU and trade independently with China.
However, although they initially accepted the free movement of people, a referendum in 2014 overturned this. The Swiss government has set a February 2017 deadline for it to be implemented.
Canada, meanwhile, has a free-trade deal with the EU after signing the Comprehensive Economic and Trade Agreement.
Turkey, despite not being a member of the European Union, trades with the 28-nation block as part of a "customs union" - an agreement to not impose tariffs on each other's goods.
The country also voted to keep control over its own borders.