No. Lambdas are a language notation representing a computation with parameterized inputs. A closure is a lower level <i>data structure</i> in the language implementation, which a lambda may or may not compile into. A closure consists of a chunk of code (whether s-expressions to be interpreted, vm bytecode, or native object code) together with a record that provides the locations of the code chunk&#x27;s free variables in the surrounding environment. (In Scheme, variables bind to locations, not values.) If a lambda has no free variables, then the chunk of code itself suffices to represent it, and this code may be inlined, optimized away, jumped into instead of &quot;called&quot; when it appears in tail position, etc.<p>One of the things that makes lambda so powerful is that it does not force a particular implementation on the language implementer, and allows for plenty of room for optimization.