Generate a topic word for the given sentence. A topic word is usually the name of a person, place, animal, concept or object the sentence is focusing on.

in cryptography, a pre-shared key or psk is a shared secret which was previously shared between the two parties using some secure channel before it is used.
pre-shared key

hadstock is a village and civil parish in uttlesford, essex, england.
hadstock

stefan demert (15 december 1939 – 9 july 2018) was a swedish singer-songwriter and musician.

stefan demert

