C++: What are the most important C++ best practices?

Core practices:

1. RAII — tie resource lifetime to object lifetime
2. Use smart pointers — unique_ptr by default
3. Prefer value semantics — avoid unnecessary pointers
4. Use const — make everything const that can be
5. Avoid raw loops — use algorithms and ranges

Modern C++: 6. Use auto — when type is obvious 7. Use structured bindings — cleaner decomposition 8. Use constexpr — compile-time computation 9. Use concepts — constrain templates 10. Use std::optional/std::variant — safer alternatives

Safety: 11. Bounds checking — use .at() or std::span 12. Initialize everything — no uninitialized variables 13. Use RAII wrappers — lock_guard, unique_lock 14. Avoid using namespace std — in headers 15. Error handling — std::expected or exceptions