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+.. highlight:: cpp
+
+.. _lang-randomseed:
+
+randomSeed()
+============
+
+``randomSeed()`` initializes the `pseudorandom number generator
+<http://en.wikipedia.org/wiki/Pseudorandom_number_generator>`_,
+causing it to start at an arbitrary point in its random sequence.
+This sequence, while very long, and random, is always the same.
+
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: randomSeed
+
+Discussion
+----------
+
+If it is important for a sequence of values generated by
+:ref:`random() <lang-random>` to differ, on subsequent executions of a
+sketch, use ``randomSeed()`` to initialize the random number generator
+with a fairly random input, such as :ref:`analogRead()
+<lang-analogread>` on an unconnected pin.
+
+Conversely, it can occasionally be useful to use pseudorandom
+sequences that repeat exactly. This can be accomplished by calling
+``randomSeed()`` with a fixed number, before starting the random
+sequence.
+
+Example
+-------
+
+The following sketch initializes the random seed based on an :ref:`ADC
+<adc>` reading of pin 0.  If this pin is unconnected, the Sketch
+should print different values to the :ref:`serial monitor
+<ide-serial-monitor>` each time it is run::
+
+    long randNumber;
+
+    void setup() {
+      pinMode(0, INPUT_ANALOG);
+      randomSeed(analogRead(0));
+    }
+
+    void loop() {
+      randNumber = random(300);
+      SerialUSB.println(randNumber);
+
+      delay(50);
+    }
+
+See Also
+--------
+
+-  :ref:`random() <lang-random>`
+
+.. include:: cc-attribution.txt