Which author co-wrote "The Communist Manifesto" alongside Karl Marx?

The author who co-wrote The Communist Manifesto alongside Karl Marx is Friedrich Engels. Engels was a German philosopher, social scientist, and political theorist, and he collaborated closely with Marx in developing Marxist theory. Engels provided crucial financial and intellectual support to Marx and played a significant role in editing and expanding their joint work, including The Communist Manifesto. Engels's contributions helped shape and articulate the fundamental ideas of communism, making him an essential co-author of this influential political manifesto.