, better known simply as Dida (Brazilian Portuguese: [ˈdʒidɐ]), is a Brazilian former football goalkeeper and goalkeeping coach. He started his senior club career in Brazil in the early 1990s with Vitória before moving to Cruzeiro and Corinthians. He is perhaps best remembered for his ten-year stint with AC Milan from 2000 to 2010, where he established himself as one of the world's best goalkeepers and won multiple trophies and individual awards with the club, including one Serie A title (Scudetto) and twice the UEFA Champions League, with the first of those victories coming after he saved three penalties in the 2003 final against Serie A rivals Juventus, and is one of four Milan keepers with 300 career appearances. After a two-year absence from playing, he returned to Brazil in 2012, appearing for three teams—Portuguesa, Grêmio and Internacional—in as many seasons. He returned to Milan to serve as their goalkeeping coach from 2020 to 2022.

At international level, Dida earned 91 caps in eleven years with the Brazil national team, winning the FIFA World Cup and an Olympic medal, while he is the most successful player in the history of the FIFA Confederations Cup. He notably broke a colour barrier during the 1999 Copa América by being the Seleção's first Afro-Brazilian starting goalkeeper since Moacir Barbosa half a century earlier and in 2006 became the first goalkeeper of this ethnicity to start for Brazil in a FIFA World Cup finals tournament since 1950, again when Barbosa was between the sticks.

Considered one of the best goalkeepers of all time, Dida was the inaugural FIFPro Goalkeeper of the Year. He is additionally rated among the all-time greats in the position for Brazil alongside Alisson Becker, Marcos, Rogério Ceni, Cláudio Taffarel and Gilmar. Dida has been credited with helping end the prejudice against black goalkeepers in Brazilian club football due to his success in Europe, and upon joining Internacional in 2014, became the first Afro-Brazilian keeper to play for the club in 43 years.