OpenAI Codex is an advanced AI system developed by OpenAI that translates natural language into code. This AI model is a successor to GPT-3 and its training data includes both natural language and billions of lines of publicly available source code, including Python and over a dozen other programming languages.

OpenAI Codex differs notably from GPT-3 in that, while GPT-3's main ability lies in generating natural language in response to a prompt, Codex actually produces working code and interprets simple commands in natural language to execute them.

This broadens its utility for a range of tasks including refactoring code, explaining code, and even writing code from natural language instructions. The Codex is proficient in more than a dozen programming languages, making it versatile across a variety of tasks and programming environments.

The model has shown success in aiding developers in splitting complex problems into simpler tasks and mapping these to existing code solutions or features.

In essence, OpenAI Codex creates an intuitive bridge between human language and the language of code which allows for enhanced communication with and operation of software systems.