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+When called with just the `key` argument, return a random element from the set
+value stored at `key`.
+
+Starting from Redis version 2.6, when called with the additional `count`
+argument, return an array of `count` **distinct elements** if `count` is
+positive. If called with a negative `count` the behavior changes and the command
+is allowed to return the **same element multiple times**. In this case the
+number of returned elements is the absolute value of the specified `count`.
+
+When called with just the key argument, the operation is similar to `SPOP`,
+however while `SPOP` also removes the randomly selected element from the set,
+`SRANDMEMBER` will just return a random element without altering the original
+set in any way.
+
+@return
+
+@bulk-string-reply: without the additional `count` argument the command returns
+a Bulk Reply with the randomly selected element, or `nil` when `key` does not
+exist. @array-reply: when the additional `count` argument is passed the command
+returns an array of elements, or an empty array when `key` does not exist.
+
+@examples
+
+```cli
+SADD myset one two three
+SRANDMEMBER myset
+SRANDMEMBER myset 2
+SRANDMEMBER myset -5
+```
+
+## Specification of the behavior when count is passed
+
+When a count argument is passed and is positive, the elements are returned as if
+every selected element is removed from the set (like the extraction of numbers
+in the game of Bingo). However elements are **not removed** from the Set. So
+basically:
+
+- No repeated elements are returned.
+- If count is bigger than the number of elements inside the Set, the command
+  will only return the whole set without additional elements.
+
+When instead the count is negative, the behavior changes and the extraction
+happens as if you put the extracted element inside the bag again after every
+extraction, so repeated elements are possible, and the number of elements
+requested is always returned as we can repeat the same elements again and again,
+with the exception of an empty Set (non existing key) that will always produce
+an empty array as a result.
+
+## Distribution of returned elements
+
+The distribution of the returned elements is far from perfect when the number of
+elements in the set is small, this is due to the fact that we used an
+approximated random element function that does not really guarantees good
+distribution.
+
+The algorithm used, that is implemented inside dict.c, samples the hash table
+buckets to find a non-empty one. Once a non empty bucket is found, since we use
+chaining in our hash table implementation, the number of elements inside the
+bucket is checked and a random element is selected.
+
+This means that if you have two non-empty buckets in the entire hash table, and
+one has three elements while one has just one, the element that is alone in its
+bucket will be returned with much higher probability.