Generally, the newer languages are easier to write code in / have less things for a developer to worry about. This usually comes at a performance cost, and newer languages have less cumulative time to weed out bugs in the language itself. So older languages are used in mission critical applications and where high performance is more important than ease/speed of development.
There are so many newer languages because different people have competing ideas about what makes a language easier to use/faster to develop in and what tradeoffs are acceptable to achieve that.
There are also some languages that are written to make a specific task easier to do, but aren’t really useful in general applications. And languages which are considered teaching languages which are intentionally more difficult to develop in because they expose the underlying concepts of computer science better.
Credentials: Staff Software Engineer with 25+ years code writing experience in over a dozen languages.
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