In 'Arrival', what is the name of the linguist who learns the alien language?

In 'Arrival', the linguist who learns the alien language is Louise Banks.

Played by Amy Adams, Banks is recruited by the U.S. Army after twelve extraterrestrial spacecraft appear around Earth. Working with physicist Ian Donnelly, she attempts to communicate with the seven-limbed aliens known as heptapods. Her approach begins with basic words and objects before developing into the aliens' complex written system of circular logograms.

Banks eventually realizes that the heptapods' language does more than communicate information: learning it changes how she experiences time. This insight helps her understand that the aliens' apparent “weapon” is actually a tool intended to help humanity. A common mix-up is confusing Banks with Ian Donnelly, who is her scientific partner, or Colonel Weber, the military officer who recruits her. Louise Banks is also the narrator and central linguist in Ted Chiang's 1998 novella 'Story of Your Life', which inspired the film.