This is the 39th most frequent Hungarian word.
akik
"Akik" means "who" (plural, relative pronoun).
In this sentence, 'akik' is a relative pronoun referring to 'azon emberek' ('those people'), serving to specify the identity of his friends.
Barátai azok az emberek, akik mindig mellette állnak.
His friends are those people who always stand by him.
In this example, 'akik' functions as a relative pronoun referring to 'Az orvosok' ('The doctors'), introducing additional information about them.
Az orvosok, akik fáradhatatlanul dolgoznak, jobbá teszik a világot.
The doctors, who work tirelessly, make the world a better place.
Here, 'akik' is used as a relative pronoun referring to 'Azok az emberek' ('those people'), introducing a subordinate clause to provide more details about them.