Models walk the runway at the Fendi show during Milan Fashion Week Fall/Winter 2017/18. Photo By Antonio De Moraes Barros Filho / Wireimage

The world's top fashion brands are doing some serious courting of social media-savvy youngsters, with Italy's Fendi the latest to unveil a hip website designed for millennials.

The Roman fashion house is one of many hoping to build up a loyal support base among the generation born after 1980, who came of age in the 21st century and have the last word on what's cool.

"F is for ..." is a new section on Fendi's website that offers tips on where to hang out in Rome and New York, has interviews with "freaks" who talk about their passions, and features photoboards of vintage items and new Fendi designs.

Cristina Monfardini, Fendi Vice President of Communication, told AFP the idea was to find a way to talk the same language as a generation that may not have the cash to splash on top brands but has massive power to pass the word.

Sometimes dubbed "the Y Generation" and often maligned by grumbling older generations as variously lazy or smartphone-obsessed, they have different values from traditional fashionistas and "move very fast" from trend to trend, Monfardini says.

"Fashion is a very structured world under certain points of view, and I think in order to get to know them (millennials) and get very close to them you need to be very humble," she said in an interview on the sidelines of Milan Fashion Week.

The trick is to avoid appearing to dictate fashion to them but "put them on the same level, just be open and listen to them".