Short answers, pulled from the story.
Hideo Kojima created Solid Snake, and the original Metal Gear game released in 1987. The character was initially designed as a pastiche of action movie heroes like Michael Biehn from The Terminator.
By 2014, Kojima revealed the true origin of the name came from snakes being symbols of stealth rather than just an homage to Kurt Russell's Snake Plissken. The name symbolizes stealth through the snake while contrasting that image with solidity.
In Metal Gear Solid 4: Guns of the Patriots which arrived in 2008, Snake appeared as an elderly man despite being only forty-two years old due to genetic manipulation. His life had been artificially shortened as part of the cloning process so his genes could not be used as weapons later.
His real name is David, a tribute to the film 2001: A Space Odyssey that shares the same name with his English voice actor David Hayter. Akio Otsuka voiced Solid Snake in the Japanese version while David Hayter provided the English adaptation.
A 2024 poll conducted by BAFTA with around 4,000 respondents named Solid Snake as the fourteenth most iconic video-game character of all time. Electronic Gaming Monthly listed him number one as the top ten video game characters of all time in 2005.