Dear JohnY_MSK,

Good day! Thank you for posting to Microsoft Community. We are happy to help you.

In the Microsoft Teams desktop app, the terms “Teams version” and “Client version” refer to different aspects:

1. Teams Version indicates the specific build or release of the Microsoft Teams application. It includes updates, new features, functionalities and bug fixes that have been implemented over time. You can find the version number in the app settings, which helps you ensure you’re using the latest version with all the current features and improvements. Refer to Version update history for Teams app deployments - Office release notes | Microsoft Learn.
2. Client Version is a more technical term that refers to the underlying framework or components used to run the Teams application. It might include information about the operating system, browser, or other dependencies, refers to the specific version of the underlying client software that interacts with the Teams backend. Microsoft Teams can be accessed through different clients, such as the desktop app, web client, or mobile app. Each client might have slight variations in features and performance. For example, the desktop client is typically more feature-rich and performs better for intensive tasks compared to the web client. Refer to Overview of the new Microsoft Teams client - Microsoft Teams | Microsoft Learn.

I hope the information helps! If there is any update or I misunderstand you, please feel free to let me know. I will continue to assist you. Your understanding and co-operation are highly appreciated.