Key words
ACL - Access Control List
IDS - Intrusion Dection Systems
ASLR - Address-Space Layout Randomization
CVE - Common Vulnerabilities & Exposures
Rootkit - Rootkit - Wiki
E.g. I have to prove that I own the key to Room A, but I don't want to show you it or give it to you. Both of us know a specific thing in A, so I can open the door and fetch it and show the thing to you.Then I can prove I own the key to some extent.