Daniel Mark Lewin (Hebrew: דניאל "דני" מארק לוין; May 14, 1970 – September 11, 2001) was an American and Israeli mathematician and entrepreneur who co-founded Akamai Technologies.

[5] Lewin was the company's chief technology officer and a board member, and achieved great wealth during the height of the Internet boom.

[11] The 9/11 Commission speculated that Lewin, who had served four years in the Israeli military, may have attempted to confront Atta or Omari, who had been seated in front of him, not knowing that al-Suqami was sitting just behind him.

[14] After his death, the intersection of Main and Vassar Streets in Cambridge, Massachusetts, was renamed Danny Lewin Square in his honor.

[18] According to Raskin, "Because of Akamai, almost every major news site remained up and running [on September 11], a feat that proved everything Danny promised to be possible".