diff --git a/README.md b/README.md
index d4d17a56..db5ac6a1 100644
--- a/README.md
+++ b/README.md
@@ -87,7 +87,7 @@ The function output is dictated by the function itself.
 | stddev()                  | Provides the standard deviation value of an array of numbers        | Double    |
 | length()                  | Provides the length of an array                                     | Integer   |
 | sum()                     | Provides the sum value of an array of numbers                       | Double    |
-
+| keys()                    | Provides the property keys (An alternative for terminal tilde `~`)  | `Set<E>`  |
 
 Filter Operators
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