profiles - A profile is a set of configuration options that can be used to customize the way Rust code is compiled.

Cargo provides two built-in profiles: dev and release. The dev profile is used every time you run cargo build, cargo run or cargo test. It's aimed at local development, therefore it sacrifices runtime performance in favor of faster compilation times and a better debugging experience. The release profile, instead, is optimized for runtime performance but incurs longer compilation times. You need to explicitly request via the --release flag—e.g. cargo build --release or cargo run --release.

ownership, references, and borrowing - Rust's system ensures memory safety without needing a garbage collector. It prevents data races and ensures that memory is cleaned up when no longer needed.

• Ownership: Each value in Rust has a single owner, and when the owner goes out of scope, the value is dropped.
• References: Allow you to refer to some value without taking ownership. They can be immutable (&T) or mutable (&mut T).
• Borrowing: When you pass references to functions, you're borrowing the value. Mutable borrows (&mut T) allow you to modify the value.

memory management - Efficient memory management is key for performance and safety. Rust's system avoids common bugs like null pointer dereferencing, double frees, and use-after-free.

• Stack: Used for fixed-size, simple data (like integers). It’s fast because the allocation and deallocation happen in a predictable manner.
• Heap: Used for dynamic, complex data (like String or Vec). It’s slower due to the need for allocating and freeing memory.
• Pointers: Box<T>, Rc<T>, and Arc<T> are types that manage heap data. Box<T> provides single ownership, Rc<T> and Arc<T> provide reference-counted ownership.
• Destructors: Automatically clean up resources when a value goes out of scope using Rust’s Drop trait.