Mixed mode exists to maintain backward compatibility. However, mixed mode limits the system to the constraints that are imposed by earlier software releases.
混合模式的存在是为了保留回溯相容性，但混合模式限制了系统对旧版软体约束的使用。
2
On the other hand, online app vendors like Zoho are extending the apps to the offline mode for backward compatibility.
另一方面，类似Zoho这样的在线应用提供商正为了向后兼容将这些应用拓展到离线模式。
3
Microsoft promises Windows 7 will support almost every piece of software compatible with XP, and in the few cases it doesn’t, there’s an XP virtualization mode ensuring backward compatibility.