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+.. highlight:: cpp
+
+.. _arduino-assignment:
+
+= assignment operator (single equal sign)
+=========================================
+
+Stores the value to the right of the equal sign in the variable to
+the left of the equal sign.
+
+
+The single equal sign in the C++ programming language is called the
+assignment operator. It has a different meaning than in algebra
+class where it indicated an equation or equality. The assignment
+operator tells the microcontroller to evaluate whatever value or
+expression is on the right side of the equal sign, and store it in
+the variable to the left of the equal sign [#fgross]_.
+
+
+
+Example
+-------
+
+::
+
+ int sensVal; // declare an integer variable named sensVal
+ senVal = analogRead(0); // store the (digitized) input voltage at analog pin 0 in SensVal
+
+
+
+Programming Tips
+----------------
+
+The variable on the left side of the assignment operator ( = sign )
+needs to be able to hold the value stored in it. If it is not large
+enough to hold a value, the value stored in the variable will be
+incorrect.
+
+
+
+Don't confuse the assignment operator [ = ] (single equal sign)
+with the comparison operator [ == ] (double equal signs), which
+evaluates whether two expressions are equal.
+
+
+
+See Also
+--------
+
+
+- `if (comparison operators) <http://arduino.cc/en/Reference/If>`_
+- `char <http://arduino.cc/en/Reference/Char>`_
+- `int <http://arduino.cc/en/Reference/Int>`_
+- `long <http://arduino.cc/en/Reference/Long>`_
+
+
+.. rubric:: Footnotes
+
+ Experienced C++ programmers know this to be an oversimplification
+ of what happens when the variable on the left hand side is an
+ object. See Richard Gillam's wonderful and scary `The Anatomy of
+ the Assignment Operator
+ <http://icu-project.org/docs/papers/cpp_report/the_anatomy_of_the_assignment_operator.html>`_