Even though this report tries to present accessibility from many different angles, there are still loads of topics that just barely got mentioned. There are about a dozen hook types and only two of the most essential in terms of accessibility were discussed in this essay. Secondly, Microsoft has built a high-levle object-oriented API called MSAA (Microsoft active accessibility) that applcation developers can use to make custom controls accessible to screen readers., Even though MSAA is a great concept in general, accordding to the sscreen reader venders they still don't get enough info from the operating system so Microsoft still has a long way to go. Leading screen reader manufacturers are resorting to screen interceptor drivers and shape detection to make custom, non MSAA compliant controls even relatively accessible. We also omited the different types of custom controls and newer Win32 common controls such as trees and sliders mainly due to their complexity.
Performance optimization is also one critical area in screen reading. As handling systemwide events in hook functions takes a lot of CPU time, one should hook as few messages and return as fast as possible. Even assembler might be a valid optimization technique.
Even though we couldn't dive into everything in this paper, I still sincerely hope this report enlightened the use of Windows hooks, dynamic link libraries and how screen readres work in practise.