Immutability is a quite old concept that is mostly related to the functional programming, however, it’s also (maybe not so widely) used in the object oriented programming. An immutable variable/object can not be mutated, which means that once it’s been initialized it will never change it’s original value/reference (unless it’s deallocated). This approach results in some great benefits such as out of the box thread safety, yet in the OOP world, it does seem to be quite often abused or even not used at al...