1. Authentication Library: The key difference between adal and msal is that adal (Azure Active Directory Authentication Library) primarily handles authentication for Azure Active Directory v1.0 whereas msal (Microsoft Authentication Library) is designed to work with Azure AD v2.0 endpoints, providing support for newer features and protocols.

2. Token Management: Another significant difference lies in how adal and msal handle token management. Adal uses tokens that are specific to a particular resource, while msal uses a single token for all resources, providing a more streamlined approach to token acquisition and management.

3. Cross-platform Support: MSAL offers better cross-platform support compared to adal. MSAL supports various platforms like C#, JavaScript, Java, Python, and more, making it more versatile and suitable for a wider range of applications.

4. Library Design: Adal is a .NET-centric library and may have limitations when used in other programming languages, whereas msal is designed to be more flexible and adaptable for different programming languages and platforms.

5. Scopes Handling: MSAL introduces the concept of scopes, enabling more fine-grained control over the permissions requested by an application. Adal does not have the concept of scopes and operates based on resource-specific permissions.

6. Version Compatibility: MSAL offers better compatibility with newer versions of Azure AD endpoints and features, ensuring that applications built with msal are more future-proof compared to those built with adal.

In Summary, adal and msal differ in authentication library compatibility, token management, cross-platform support, library design, scopes handling, and version compatibility, making each suitable for different use cases.