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+# Cryptographic Hash Functions
+
+## Random Jargon
+
+_If you made it this far you know what all of this is but we need these terms because "muh academic vernacular"_
+
+* Variable Length Input
+* Fixed size output
+
+```python
+a = {
+	'first',
+	'second',
+}
+```
+Both `first` & `second` as inputs result in distinct references of the same size.
+
+* One-way property
+
+You should **not** be able to use a hash result(i.e. reference) to find an input. 
+
+In English: _Only inputs can find outputs, not the other way around._
+
+* Two-way property/ Collision-free Property
+
+**2** identical data inputs will map to the same output