First, pre-bedding
(1) SDK and API
SDK : a collection of software development tools to build applications software development kit (Software Development Kit), some packages are generally being used for a particular software engineers, software framework, hardware platform, operating system, etc.
API functions : Windows operating system to provide application programming interfaces (Application Programing Interface)
Windows application API functions are implemented by C language, all Windows functions were declared in the header file Windows.h.
(2) and the window handle
Window : The window is a rectangular area on the screen, the interface is a Windows application that interacts with the user, using a window can accept user input and display output.
An application window usually includes the title bar, menu bar, system menu, minimize box, maximize box, adjustable border, and some have a scroll bar.
Handle : In Windows programs, there are a variety of resources (windows, icons, cursors, brushes, etc.), will allocate memory for them when creating these resources system and return the identification number of these resources, namely handle. For example, icon handle (HICON), the cursor handle (HCURSOR), brush handles (HBRUSH).
(3) message and a message queue
Windows programming is an event-driven programming model approach, mainly based on the message.
After every Windows application begins execution system for the program will create a message queue, the message queue is used to store messages created by this program window.