Search notes:

TabTip.exe

TabTip.exe is the touch keyboard and handwriting panel.
Possibly, Tip stands for text input panel or tablet input panel.
This EXE is referenced under HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\App Paths.

See also

The registry keys HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\TabletTip and HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\CTF\TIP
The TabletInputService service
osk.exe

Index