The Welshman retires with 963 appearances to his name, having racked up an incredible 13 Premier League titles, four FA Cups and two UEFA Champions League crowns to become by far the club's most decorated player.
In an open letter to the club's fans, he said: "Today is a fantastic day for Manchester United. Louis van Gaal is a great appointment and let me begin by telling you how delighted I am to be working with someone of his calibre.
"I would also like to take this opportunity to announce my retirement from professional football and embark upon a new and exciting chapter in my life, as assistant manager of Manchester United.
"I am immensely proud, honoured and fortunate to have represented the biggest club in the world 963 times and Wales 64 times."
He was immediately thrust into the United first team by Alex Ferguson - becoming the first of the legendary 'Class of 1992' to break into the side.
Perhaps Giggs' most memorable contribution came on April 14, 1999 with United and Arsenal locked at 1-1 in extra-time of their FA Cup semi-final replay.
He also managed the club on an interim basis this season after David Moyes' sacking - highlighting the esteem and regard he held at Old Trafford.
