Niche tourism: Special-interest tourism for a relatively small group of tourists. Examples include adventure, ecotourism, agro-tourism, heritage, medical, tribal, dark tourism, etc.

• Example: Ecotourism focuses on nature and sustainability, like bird-watching in Costa Rica.

Mass tourism: Package tours with fixed itineraries and guided stops. They offer maximum familiarity and minimum novelty.

A form of niche tourism involving travel to remote areas with some level of perceived or real risk.

It attracts high-value customers who are willing to pay a hefty amount for unique experiences, like $50,000 to climb Mount Everest.

A large percentage of revenue spent in this sector remains in the destination, supporting local economies and sustainable practices.

It has three categories: soft (sightseeing), hard (crossing the Greenland ice sheet), and other.

Greenland has seen a 195% increase in adventure tourism from 2010 to 2014, targeting the North American market.

Examples of attractions include exploring Viking ruins (for cultural tourists), bird watching (nature tourists), or heli-skiing (extreme adventure tourists).

Some tourists are attracted to locations featured in popular TV shows and films, like "Game of Thrones" in Northern Ireland or "Lord of the Rings" in New Zealand. Other locations, like Disneyland or Universal Studios, create experiences based on film/TV concepts.