Information on dealing sensible information?

[Alexander]

I need to find some information on how a program can deal sensible
information on users' computers in such a way that it is not directly
accessible and/or modifiable? Any information is appreciated. Thanks

 

[Francesco S. Carta]

I need to find some information on how a program can deal sensible
information on users' computers in such a way that it is not directly
accessible and/or modifiable? Any information is appreciated. Thanks

Not directly accessible and modifiable by whom, and where? You need to
post more details about your question, and even when you'll do that,
chances are that you'll be off topic - all of your concerns should boil
down to encryption methods and memory protection, none of them is
topical here. Search the web for starters.