Win32 APIs

Function	Description
Keybd_event	Synthesizes a keystroke given a VK, a scan code, etc., (Superceded by the SendInput API)
MapVirtualKey	Maps between scan codes, VKs, and characters for the current keyboard layout.
MapVirtualKeyEx	Maps between scan codes, VKs, and characters for a specified keyboard layout (layout must be loaded)
OemKeyScan	Maps OEMASCII codes to OEM scan codes and shift states
SendInput	Synthesizes a keystroke given a VK, a scan code, etc.,
ToAscii	Maps a VK and shift state to a character on the current keyboard layout's associated codepage.
ToAsciiEx	Maps a VK and shift state to a character on the specified keyboard layout's associated codepage (layout must be loaded)
ToUnicode	Maps a VK and shift state to a Unicode character per the current keyboard layout.
ToUnicodeEx	Maps a VK and shift state to a Unicode character per the specified keyboard layout (layout must be loaded)
VkKeyScan	Converts a character to a VK and shift state for the current keyboard layout
VkKeyScanEx	Converts a character to a VK and shift state for the specified keyboard layout (layout must be loaded)

Table : Keyboard Input Functions and what they do

The functions in Table are interesting in that when you read the descriptions, the functions appear to be duplicates of each other. However, once you start needing these functions in an application, you will see the small differences between these different functions can actually have a great deal of importance for obtaining the features you need.