Following the publication of a heartfelt personal letter in which the Apple CEO revealed his sexual orientation publicly for the first time, Tim Cook has been showered with praise from coworkers, competitors, celebrities and more.

Cook made his unexpected announcement on Thursday in an essay published by Bloomberg, saying that he is "proud" to be gay. The Apple chief executive said being gay has given him perspective on what it means to be a minority, and has given him "the skin of a rhinoceros" — a valuable asset when leading a major corporation.

Among those praising Cook on Thursday was Phil Schiller, Apple's senior vice president of worldwide product marketing, who called his boss "courageous." The marketing chief tweeted at Cook and said he is "proud to work for you and be your friend."

Apple Senior Vice President of Internet Software and Services Eddy Cue also publicly extolled Cook, calling him a "friend and colleague."

Cook also earned support from former U.S. President Bill Clinton, who tweeted at the Apple CEO, calling him a fellow "son of the South and sports fanatic." Clinton was born and raised in Arkansas, where he eventually became governor, while Cook hails from Alabama.

From one son of the South and sports fanatic to another, my hat's off to you, @Tim_cook. http://t.co/1dXvRa2Nhu — Bill Clinton (@billclinton) October 30, 2014

Former U.S. Representative Barney Frank also spoke out in an interview with CNBC, in which he said Cook's announcement is "extraordinarily important." Frank served as a member of the U.S. House of Representatives for more than 30 years, and spent a majority of that time as an openly gay politician, after coming out publicly in 1987.

Frank said that Cook's stature as being one of the most important business leaders in America will go a long way in breaking down stereotypes about people of different sexual orientations.

"That does such an enormous amount to diminish the negative feelings," Frank said. "I am very grateful for him doing it."

Satya Nadella, CEO of rival Microsoft, also expressed support for Cook on Thursday. The head of the Redmond, Wash., software giant took to Twitter to say he is "inspired by" Cook and his essay.

Inspired by @tim_cook: "Life's most persistent & urgent question is 'What are you doing for others?'" http://t.co/wjzW5QPxqY via @BW — Satya Nadella (@satyanadella) October 30, 2014