     SPINNING
   };
   static Mode mode = Mode::SETTING_TIME;                // initialization over assignment; set SETTING_TIME as the first mode!
-  /* Perform operations with data of the same type, to
-    boost performance by not needing to implicitly typecast
+  /* Perform operations with data of the same type, will boost processing speed
+    by removing implicit typecasts, but if datatype is not the smallest that can
+    hold the maximum value of that data, then this comes at a cost to SRAM.
     */
-  static unsigned long setDuration;
+  static unsigned long setDuration;                     // will be measured in ms so unsigned long is appropriate
   static unsigned long spinningStartTime;               // point in time when countdown starts i.e. when wpb pressed the 2nd time
-  static uint8_t motorSpeed;
+  static uint8_t motorSpeed;                            // uint8_t == typedef for an unsigned 8-bit integer aka a char or a byte
 
   switch(mode)
   {


namespace
{
    LiquidCrystal lcd
    = LiquidCrystal(12, 11, 5, 4, 3, 6);                  // initialize LC object with the numbers of the interface pins

    // White Pushbutton
    const uint8_t WPB_IN_PIN = 2, WPB_LED_PIN = 13;


    const uint8_t MOTOR_PIN = 9;
    const uint8_t POT_PIN = A5;

    //Function prototypes
    /* It's good practice to define the prototypes yourself, rather than letting
