External environment refers to the major factors and forces outside the organization that have the potential to significantly affect the performance of an organization. External environment is divided into two parts i.e. mega environment or general environment and specific or task environment.
_tcscat is a C function, to concatenate C-style strings; CString is a class (which has built in concatenation via operator+), not a C-style string.
References (C++) The new home for Visual Studio documentation is Visual Studio 2017 Documentation on docs.microsoft.com. The latest version of this topic can be found at References (C++). A reference, like a pointer, stores the address of an object that is located elsewhere in memory. Unlike a pointer, a reference after it is initialized cannot be made to refer to a different object or set to null. There are two kinds of references: lvalue references which refer to a named variable and rvalue references which refer to a temporary object. The & operator signifies an lvalue reference and the && operator signifies either an rvalue reference, or a universal reference (either rvalue or lvalue) depending on the context.