*Lambda terms*: lambda terms are written with a backslash, thus: `((\x (\y x)) z)`.
If you click "Reduce", the system will produce a lambda term that is guaranteed to be reduction equivalent (`<~~>`) with the original term. So `((\x (\y x)) z)` reduces to (a lambda term equivalent to) `(\y z)`.
-*Let*: in order to make building a more elaborate system easier, it is possible to define values using `let`.
+*Let*: in order to make building a more elaborate set of terms easier, it is possible to define values using `let`.
In this toy system, `let`s should only be used at the beginning of a file. If we have, for intance,
let true = (\x (\y x)) in
((true yes) no)
the result is `yes`. Things to watch out for: the expression after the equal sign must have balanced parentheses,
-and the "in" is obligatory. The system will still produce a result, but it won't make much sense.
+and the "in" is obligatory. If you violate these rules, the system will still produce a result, but it won't make much sense.
*Abbreviations*, **NOT**: No abbreviations work. So `\xy.yxx` must be written `(\x (\y ((y x) x)))`. (As in Scheme or Racket.)