A positional numeral system with a radix, or base, of 16, using sixteen distinct symbols, typically the numbers 0 to 9 to represent values zero to nine, and the letters A to F (or a to f) to represent values ten to fifteen.

"Hexadecimal is widely used in computing and digital electronics as a human-friendly representation of binary-coded values."

A design principle in software engineering where the control flow of a program is inverted in comparison to traditional procedural programming.

"Inversion of control is often achieved through the use of frameworks, where the framework calls user-defined code rather than the user's code calling the framework."

An architectural style for designing networked applications, relying on a stateless, client-server communication model.

"RESTful web services use HTTP requests to perform CRUD operations (Create, Read, Update, Delete) on data represented in XML, JSON, or other formats."

Software that is designed to work on multiple computing platforms or operating systems.

"Cross-platform development tools enable developers to create applications that run on Windows, macOS, and Linux with a single codebase."

Software for which the original source code is made freely available and may be redistributed and modified.

"Open source software projects encourage collaboration and contributions from developers worldwide."