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LTI means “Learning Tools Interoperability”. It’s a standard that describes a way UI flow for learning platforms like edX.org to interact with learning tools, which are often third-party extensions to the core platform.
It effectively defines a protocol for the two to communicate concerns like user authentication, authorization, user information, and grades/assignments without knowing any specifics - nearly at all - about the implementation on the other end. It’s a huge abstraction layer.
This allows the seamless transfer of a user’s experience to a third party application by clicking a button or link without any additional login, navigation, or setup steps by the end-user.
Why is This Useful?
We can and do build seamless tool integrations that can handle transferring contextual information about the user, course content, and authentication. However, tailored integrations like these are costly to build and maintain. Not only that, but building for specific tools limits flexibility of course teams and Open edX site operators. LTI allows us to build a generalized integration to plug in any type of learning tool.
More Detail on What LTI Does
LTI allows a platform to include Resource Links on its pages. These links (like literally HTML hyperlinks) are responsible for “Launching” a tool. There are rules on how to structure a link and what information it needs to include. The information passed along in this link is often referred to as a “message”. There are rules on how to perform a launch. Long story short, you need to specify who you are, who the tool is, who the user is, and where the link appears on the page, all with unique identifiers. LTI also provides facilities/protocols for performing authentication during this process.
Ok But How Does It Work?
For a more technical description see LTI for Developers
What versions of LTI exist?
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