1. Operating System Compatibility: One key difference between GitHub Enterprise and IntelliJ IDEA is their operating system compatibility. GitHub Enterprise is compatible with a wide range of operating systems, including macOS, Windows, and Linux, making it a versatile choice for teams using different operating systems. On the other hand, IntelliJ IDEA is primarily designed for Java development and is compatible with macOS, Windows, and Linux as well. However, IntelliJ IDEA also offers better integration with Mac OS X compared to GitHub Enterprise, providing a more seamless development experience for macOS users.

2. Version Control: Another important difference is their approach to version control. GitHub Enterprise is a cloud-based service that utilizes Git, a distributed version control system. It provides a comprehensive suite of features for collaborative software development, such as pull requests, code reviews, and issue tracking. IntelliJ IDEA, on the other hand, is a Java IDE that supports version control systems like Git, Subversion, Mercurial, and Perforce. While it also offers some collaboration features like code review and integration with GitHub, its main focus is on providing an integrated development environment.

3. Language Support: GitHub Enterprise, being a web-based platform, supports a wide range of programming languages, including popular ones like Java, Python, JavaScript, and Ruby. It also has extensive support for markdown languages when creating project documentation. IntelliJ IDEA, as an IDE, offers strong support for Java development, including advanced features like code completion, refactoring, and debugging. It is also capable of supporting other programming languages through plugins, but its core focus remains on Java programming.

4. Continuous Integration and Deployment: GitHub Enterprise has built-in support for continuous integration and deployment (CI/CD) workflows. It integrates with popular CI/CD tools like Jenkins, Travis CI, and CircleCI, enabling automated testing, building, and deployment of software projects. On the other hand, IntelliJ IDEA provides integration with CI/CD tools as well, but it mainly focuses on providing tools and features for local development and testing, rather than full automation of the CI/CD process.

5. Team Collaboration: GitHub Enterprise is designed to facilitate team collaboration and communication. It offers features like team organization, project management, and issue tracking, allowing teams to work together efficiently. In contrast, IntelliJ IDEA primarily focuses on individual developer productivity. While it does provide some collaboration features like code review and integration with version control systems, its main emphasis is on providing a powerful and customizable development environment for individual developers.

6. Cost: Finally, the cost is a significant difference between the two. GitHub Enterprise is a paid service, and the cost is based on the number of users and the specific plan chosen. On the other hand, IntelliJ IDEA also offers both free and paid versions, with the ultimate edition providing additional features and tools. The pricing for IntelliJ IDEA is more straightforward, with a fixed cost for the ultimate edition and a free Community edition available for non-commercial use.

In summary, GitHub Enterprise excels in providing a cloud-based collaborative platform with strong version control capabilities and support for multiple operating systems, while IntelliJ IDEA focuses on providing a powerful Java IDE with advanced debugging and code development features.