Williams, who took his own life, had been struggling with depression, anxiety and the early stages of Parkinson's disease, his wife said. The 63-year-old was beloved for his roles in films like Dead Poets Society, Mrs. Doubtfire and Aladdin.
PHOTOS: Robin Williams through the years
To mark the one-year anniversary, Sarah Michelle Gellar, who was playing his daughter on the sitcom The Crazy Ones when he died, posted a photo of the bench from Good Will Hunting.
"To laugh often and much ... to know that one life has breathed easier because you lived here. This is to have succeeded," Gellar wrote, quoting Ralph Waldo Emerson. She continued, "You succeeded RW #RobinWilliams."
But Gellar's message is only the most recent of a deluge of tributes. Over the past year, messages, artwork and videos have poured in from artists, fellow entertainers and beyond. Here are just a few that resonated with fans.
Actor impersonates 18 iconic Robin Williams roles
Artist creates beautiful life-like drawing
Cast of Aladdin on Broadway sings "Friend Like Me"
Jack speech transformed into touching montage
If you are or know somebody who is having thoughts of suicide, please call the National Suicide Prevention Lifeline at 1-800-273-8255.