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+.. highlight:: cpp
+
+.. _arduino-array:
+
+Arrays
+======
+
+An array is a collection of variables that are accessed with an index
+number. Arrays in the C++ programming language, in which the Maple is
+programmed, can be complicated, but using simple arrays is relatively
+straightforward.
+
+
+Creating (Declaring) an Array
+-----------------------------
+
+All of the methods below are valid ways to create (declare) an
+array. ::
+
+      int myInts[6];
+      int myPins[] = {2, 4, 8, 3, 6};
+      int mySensVals[6] = {2, 4, -8, 3, 2};
+      char message[6] = "hello";
+
+You can declare an array without initializing it, as with myInts.  In
+the line referring to myPins, we declare an array without explicitly
+choosing a size.  The compiler counts the elements and creates an
+array of the appropriate size.
+
+Finally, you can both initialize and size your array, as in
+mySensVals. Note that when declaring an array with elements of type
+char, one more element than your initialization is required, to hold
+the required `null character <http://en.wikipedia.org/wiki/Null-terminated_string>`_.
+
+
+Accessing an Array
+------------------
+
+
+.. compound::
+
+   Arrays are **zero indexed**; that is, referring to the array
+   initialization above, the first element of the array is at index 0,
+   hence ::
+
+      mySensVals[0] == 2;
+      mySensVals[1] == 4
+
+   and so forth.
+
+It also means that in an array with ten elements, index nine is the
+last element. Hence::
+
+    int myArray[10]={9,3,2,4,3,2,7,8,9,11};
+         // myArray[9]    contains 11
+         // myArray[10]   is invalid and contains random information (other memory address)
+
+For this reason, you should be careful in accessing arrays.  Accessing
+past the end of an array (using an index number greater than your
+declared array size - 1) is reading from memory that is in use for
+other purposes. Reading from these locations is probably not going to
+do much except yield invalid data. Writing to random memory locations
+is definitely a bad idea, and can often lead to unhappy results such
+as crashes or program malfunction. This can also be a difficult bug to
+track down.
+
+Unlike Basic or Java, the C compiler does no checking to see if array
+access is within legal bounds of the array size that you have
+declared.
+
+
+To assign a value to an array:
+------------------------------
+ ::
+
+    mySensVals[0] = 10;
+
+
+To retrieve a value from an array:
+----------------------------------
+
+ ::
+
+    x = mySensVals[4];
+
+
+Arrays and ``for`` Loops
+------------------------
+
+Arrays are often manipulated inside :ref:`for loops <arduino-for>`, where
+the loop counter is used as the index for each array element. For
+example, to print the elements of an array over the serial port, you
+could do something like this::
+
+    int i;
+    for (i = 0; i < 5; i = i + 1) {
+      SerialUSB.println(myPins[i]);
+    }
+
+
+Example
+-------
+
+For a complete program that demonstrates the use of arrays, see the
+Arduino `Knight Rider example
+<http://www.arduino.cc/en/Tutorial/KnightRider>`_\ (which will run
+unmodified on the Maple).
+
+
+See also
+--------
+
+-  :ref:`Storing arrays in FLASH memory <arm-gcc-attribute-flash>`
+