how to use console/windows app without focus on it?

im going to create a KEylog applicati开发者_运维知识库on that enables me to write all data typed(keys pressed) on a text file/database how can i do this without focus on the windows app/console app?

for a reason , for all you to know, this is for my PC and im not trying to hack an account. just for me to know what they are doing on my computer.

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Find an example written in .NET here:

Processing Global Mouse and Keyboard Hooks in C#

This class allows you to tap keyboard and mouse and/or to detect their activity even when an application runs in the background or does not have any user interface at all.