In other languages say C++/Go/Python, you have a shared buffer in two threads. Both threads have mutable access to it but you know only one of them is modifying it at any point of time (because you wrote it :) ). This is not good enough in Rust. You will have to prove it to the Rust compiler at compile time that this invariant is true. In Rust you express this using its type system. Syntactically & semantically it is very different than other languages.
The implication of the above is that in Rust you will have think a lot about your code structure & data-flow upfront compared to other languages else you will hit the wall very frequently. Some people say this is how it should be anyway & others think it as impediment to the productivity. Both points are valid in my opinion ... it more of a question of cost vs benefit.