As sign language hits the Marvel Cinematic Universe: what is ISL, and where can I learn it?

Sign language, like most languages, varies from place to place - and Irish Sign Language is part of Ireland's linguistic heritage

Lauren Ridloff as Makkari in Marvel: Eternals - the MCU's first Deaf superhero.

The latest in US comic book titans Marvel's 'cinematic universe', Eternals, was released last week - placing emphasis on a variety of young heroes from a diversity of backgrounds. 

Lauren Ridloff, portraying superhero Makkari, is a successful actor, also appearing on Broadway and zombie series The Walking Dead - and is the first Deaf woman to star in the Marvel movie franchise.