[2] Williams played a lone season at North Carolina in 2004–05, helping the Tar Heels win the NCAA championship.

His tip-in with 1:26 remaining in the NCAA final against Illinois broke a 70–70 tie, propelling UNC to a 75–70 victory.

[4] In April 2005, Williams declared for the NBA draft, forgoing his final three years of college eligibility.

[19] He was a two-time recipient (2008 and 2011) of the Hawks' Jason Collier Memorial Trophy for his work as a community ambassador.

[19] He made his debut for the Jazz in their season opener on October 31, 2012, scoring 21 points in a 113–94 win over the Dallas Mavericks.

[20] He failed to surpass that scoring mark during the season, recording one other 20-point game on November 23 against the Sacramento Kings.

[23][24] He made his debut for the Hornets in their season opener on October 29, 2014, scoring 19 points 108–106 win over the Milwaukee Bucks.

His 152 three-point field goals marked the third-best single-season total ever by a Charlotte forward, trailing only Glen Rice's 1996–97 and 1995–96 seasons.

[35] On January 23, 2019, against the Memphis Grizzlies, Williams passed Rex Chapman for 12th on the franchise's scoring list.

[40] On August 29, Williams scored 12 points and grabbed 8 rebounds while coming off the bench for the Bucks in a deciding Game 5 win to end a round one matchup versus the Orlando Magic, in the NBA Bubble.

[41] On September 8, following the Bucks' second-round playoff exit after an upset loss against the Miami Heat, Williams announced his retirement from professional basketball.

For nine years, he attended summer school and some classes during the NBA season, studying both after practice and on the road.