Palms have been useful to people for thousands of years -    trunks for canoes or frames for structures; fronds for shelter, screens, baskets, or fire; the narcotic of betel nut; fibre for fires, weaving or ropes etc
For food - we use several palm seeds (dates, coconut), the crown of some palms are used as a vegetable (cabbage palms), palm oil for cooking or fuel. 

Many other seeds are eaten by birds or animals which are then consumed by us

In the landscape palms are extensively used in commercial, resort and residential applications.  A wide range of species are used to support the many types of structures, forms and colours used in modern landscape design -

tall solitary, clumping, fluffy foliage, screens, natives, stark or soft.

Palms are very useful in pool or patio areas to provide a clean open or part shade area for under planting with Cordyline, Calatheas, Bromeliads and other foliage plants.

Indoors, some species used include Cocos, Golden cane, Kentia, Rhapis and Chamaedorea species


Of course it is important to remember that most tropical palms are entirely unsuitable for temperate climates and soma palms such as Cocos (beautiful indoors, very slow growing inland or in temperate climates) are can invasive weed on the east coast