> If I remember correctly, it effectively states that variable declarations amount to reserving memory resources and nothing else; memory is not zeroed, for ins

> If I remember correctly, it effectively states that variable declarations amount to reserving memory resources and nothing else; memory is not zeroed, for instance. Not really. The idea is that any resource lifecycle management should be tied to the lifecycle of an object, therefore removing a whole class of problems. For example, when you open a file handle, the "open" operation should be tied to a class constructor, and the corresponding cleanup to the destructor. If you lock a mutex, that operation should be handled by a constructor, and the release by a destructor, so that you never forget to do the cleanup. > My question is: what makes this so useful? Looking at wikipedia, the focus seems to be on lifetime guarantees, but I'm having trouble understanding how these are useful in practice. I think Wikipedia should have an example of the things that RAII makes you avoid. Compare these two designs class Config { Config() { this->file = nullptr; } void load(const std::string& path) { this->file = open(path); } void close() { this->file->close(); } versus class Config { Config(const std::string& path) { this->file = open(path); } ~Config() { this->file->close(); } The first design makes it easy to forget calling close() before releasing the object, or maybe writing a destructor that does a double free if close() had already been called... The second design is clear, and also safe to use around exceptions. As for the comparison with another language... I don't know enough about Go, but RAII is present in a lot of object oriented languages. For example, in Python, opening a file creates a "file" object with the resource (the file handle) already allocated, and when that object refcount goes to zero, the underlying handle is released. However, because in modern languages all the "resource management" is usually done in standard libraries and memory allocation isn't done manually, programmers of those won't really hear about RAII, because all that is managed already in the standard libraries.