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- To play around with a **typed lambda calculus**, which we'll look at later
- in the course, have a look at the [Penn Lambda Calculator](http://www.ling.upenn.edu/lambda/).
- This requires installing Java, but provides a number of tools for evaluating
- lambda expressions and other linguistic forms. (Mac users will most likely
- already have Java installed.)
+Usable in your browser. It can help you check whether your answer to some of
+the homework questions works correctly.