Confidentiality, Integrity, and Availability are three terms that form the foundation for a good security base. If these terms are maintained then your security posture will be adequate. In the field of information security, this is something we (companies and individuals) all strive to attain and keep.
Confidentiality – The information is secure from outside forces or anyone who is not authorized to view. Example: your cat photos will be seen by you and only you.
Integrity – The information is the same as the last time you saw it, it did not change. Example: your folder labeled “Cat Pictures” actually contain cat pictures.
Availability – The information is easily accessible when needed. Example: the folder labeled “Cat Pictures” is easily available when needed late at night or when the urge for cat photos arise.
These are terms in a nutshell but they will be expanded upon later. The order does not matter but it is easier to remember when using the C I A method. Same with the application of these terms, the order does not apply only that they are being met.