What does hacking refer to?

Hacking specifically refers to the act of gaining unauthorized access to a computer system or file. This type of access is typically achieved by exploiting vulnerabilities in the system's security measures or by using various techniques to bypass authentication protocols. The intent can vary from malicious activities, such as stealing sensitive information or disrupting services, to more benign motivations, such as ethical hacking, which aims to improve security by identifying weaknesses.

The other options present different concepts: authorized access involves users who have permissions to interact with a system legitimately, which is not considered hacking. Accessing open-source software is a legal and often encouraged practice, while programming new software applications refers to the development process and also does not fall under the definition of hacking. Therefore, the focus on unauthorized access is what defines hacking in this context.