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+.. _arduino-static:
+
+Static
+======
+
+The static keyword is used to create variables that are visible to
+only one function. However unlike local variables that get created
+and destroyed every time a function is called, static variables
+persist beyond the function call, preserving their data between
+function calls.
+
+
+
+Variables declared as static will only be created and initialized
+the first time a function is called.
+
+
+
+Example
+-------
+
+::
+
+    
+    
+    /* RandomWalk
+    * Paul Badger 2007
+    * RandomWalk wanders up and down randomly between two
+    * endpoints. The maximum move in one loop is governed by
+    * the parameter "stepsize".
+    * A static variable is moved up and down a random amount.
+    * This technique is also known as "pink noise" and "drunken walk".
+    */
+    
+    #define randomWalkLowRange -20
+    #define randomWalkHighRange 20
+    int stepsize;
+    
+    int thisTime;
+    int total;
+    
+    void setup()
+    {
+      Serial.begin(9600);
+    }
+    
+    void loop()
+    {        //  tetst randomWalk function
+      stepsize = 5;
+      thisTime = randomWalk(stepsize);
+      Serial.println(thisTime);
+       delay(10);
+    }
+    
+    int randomWalk(int moveSize){
+      static int  place;     // variable to store value in random walk - declared static so that it stores
+                             // values in between function calls, but no other functions can change its value
+    
+      place = place + (random(-moveSize, moveSize + 1));
+    
+      if (place < randomWalkLowRange){                    // check lower and upper limits
+        place = place + (randomWalkLowRange - place);     // reflect number back in positive direction
+      }
+      else if(place > randomWalkHighRange){
+        place = place - (place - randomWalkHighRange);     // reflect number back in negative direction
+      }
+    
+      return place;
+    }
+    
+