- Python-style syntax with significant indentation

- Uniform Function Call Syntax: a.len() == a.len == len(a)

- Fully unqualified imports by default: which might seem scary to Python programmers, but works great in practice because of static typing

- All of the above makes code readable and succinct

And from a language features side:

- Compiles to C with all the architectural targets that come with it

- Compilation to C also allows for easy C interop: wrap function signatures and types and you're done

- This, in turn, means that Nim libraries can bootstrap off of the massive C ecosystem, while adding nicer APIs on top

- Extremely performant GC by default: optional Rust-style annotations can further improve performance, and you can remove all overhead and manually manage memory with C-style pointers if you'd like

- Useful compile-time templates and macros that can directly change the AST

The community is also active and helpful on IRC/Matrix/Discord/Gitter (bridged together)