Various typo fixes - only in comments, no code changes.

Marlin/Configuration.h

 //===========================================================================
 //============================= DELTA Printer ===============================
 //===========================================================================
-// For a Delta printer rplace the configuration files wilth the files in the
+// For a Delta printer replace the configuration files with the files in the
 // example_configurations/delta directory.
 //
 
 // 702= Minitronics v1.0
 // 90 = Alpha OMCA board
 // 91 = Final OMCA board
-// 301 = Rambo
+// 301= Rambo
 // 21 = Elefu Ra Board (v3)
 
 #ifndef MOTHERBOARD
 
 #define POWER_SUPPLY 1
 
-// Define this to have the electronics keep the powersupply off on startup. If you don't know what this is leave it.
+// Define this to have the electronics keep the power supply off on startup. If you don't know what this is leave it.
 // #define PS_DEFAULT_OFF
 
 //===========================================================================
 // 0 is not used
 // 1 is 100k thermistor - best choice for EPCOS 100k (4.7k pullup)
 // 2 is 200k thermistor - ATC Semitec 204GT-2 (4.7k pullup)
-// 3 is mendel-parts thermistor (4.7k pullup)
+// 3 is Mendel-parts thermistor (4.7k pullup)
 // 4 is 10k thermistor !! do not use it for a hotend. It gives bad resolution at high temp. !!
 // 5 is 100K thermistor - ATC Semitec 104GT-2 (Used in ParCan & J-Head) (4.7k pullup)
 // 6 is 100k EPCOS - Not as accurate as table 1 (created using a fluke thermocouple) (4.7k pullup)
 // 9 is 100k GE Sensing AL03006-58.2K-97-G1 (4.7k pullup)
 // 10 is 100k RS thermistor 198-961 (4.7k pullup)
 // 20 is the PT100 circuit found in the Ultimainboard V2.x
-// 60 is 100k Maker's Tool Works Kapton Bed Thermister
+// 60 is 100k Maker's Tool Works Kapton Bed Thermistor
 //
 //    1k ohm pullup tables - This is not normal, you would have to have changed out your 4.7k for 1k
 //                          (but gives greater accuracy and more stable PID)
   #define K1 0.95 //smoothing factor within the PID
   #define PID_dT ((OVERSAMPLENR * 8.0)/(F_CPU / 64.0 / 256.0)) //sampling period of the temperature routine
 
-// If you are using a preconfigured hotend then you can use one of the value sets by uncommenting it
+// If you are using a pre-configured hotend then you can use one of the value sets by uncommenting it
 // Ultimaker
     #define  DEFAULT_Kp 22.2
     #define  DEFAULT_Ki 1.08
     #define  DEFAULT_Kd 114
 
-// Makergear
+// MakerGear
 //    #define  DEFAULT_Kp 7.0
 //    #define  DEFAULT_Ki 0.1
 //    #define  DEFAULT_Kd 12
 #define ENDSTOPPULLUPS // Comment this out (using // at the start of the line) to disable the endstop pullup resistors
 
 #ifndef ENDSTOPPULLUPS
-  // fine Enstop settings: Individual Pullups. will be ignored if ENDSTOPPULLUPS is defined
+  // fine endstop settings: Individual pullups. will be ignored if ENDSTOPPULLUPS is defined
   // #define ENDSTOPPULLUP_XMAX
   // #define ENDSTOPPULLUP_YMAX
   // #define ENDSTOPPULLUP_ZMAX
   #define BACK_PROBE_BED_POSITION 180
   #define FRONT_PROBE_BED_POSITION 20
 
-  // these are the offsets to the prob relative to the extruder tip (Hotend - Probe)
+  // these are the offsets to the probe relative to the extruder tip (Hotend - Probe)
   #define X_PROBE_OFFSET_FROM_EXTRUDER -25
   #define Y_PROBE_OFFSET_FROM_EXTRUDER -29
   #define Z_PROBE_OFFSET_FROM_EXTRUDER -12.35
 //  #define PROBE_SERVO_DEACTIVATION_DELAY 300
 
 
-//If you have enabled the Bed Auto Levelling and are using the same Z Probe for Z Homing,
+//If you have enabled the Bed Auto Leveling and are using the same Z Probe for Z Homing,
 //it is highly recommended you let this Z_SAFE_HOMING enabled!!!
 
   #define Z_SAFE_HOMING   // This feature is meant to avoid Z homing with probe outside the bed area.
 //#define BED_CENTER_AT_0_0  // If defined, the center of the bed is at (X=0, Y=0)
 
 //Manual homing switch locations:
-// For deltabots this means top and center of the cartesian print volume.
+// For deltabots this means top and center of the Cartesian print volume.
 #define MANUAL_X_HOME_POS 0
 #define MANUAL_Y_HOME_POS 0
 #define MANUAL_Z_HOME_POS 0
 
 #define DEFAULT_AXIS_STEPS_PER_UNIT   {78.7402,78.7402,200.0*8/3,760*1.1}  // default steps per unit for Ultimaker
 #define DEFAULT_MAX_FEEDRATE          {500, 500, 5, 25}    // (mm/sec)
-#define DEFAULT_MAX_ACCELERATION      {9000,9000,100,10000}    // X, Y, Z, E maximum start speed for accelerated moves. E default values are good for skeinforge 40+, for older versions raise them a lot.
+#define DEFAULT_MAX_ACCELERATION      {9000,9000,100,10000}    // X, Y, Z, E maximum start speed for accelerated moves. E default values are good for Skeinforge 40+, for older versions raise them a lot.
 
 #define DEFAULT_ACCELERATION          3000    // X, Y, Z and E max acceleration in mm/s^2 for printing moves
 #define DEFAULT_RETRACT_ACCELERATION  3000   // X, Y, Z and E max acceleration in mm/s^2 for retracts
 //===========================================================================
 
 // EEPROM
-// the microcontroller can store settings in the EEPROM, e.g. max velocity...
-// M500 - stores paramters in EEPROM
+// The microcontroller can store settings in the EEPROM, e.g. max velocity...
+// M500 - stores parameters in EEPROM
 // M501 - reads parameters from EEPROM (if you need reset them after you changed them temporarily).
 // M502 - reverts to the default "factory settings".  You still need to store them in EEPROM afterwards if you want to.
-//define this to enable eeprom support
+//define this to enable EEPROM support
 //#define EEPROM_SETTINGS
 //to disable EEPROM Serial responses and decrease program space by ~1700 byte: comment this out:
 // please keep turned on if you can.
 #define ABS_PREHEAT_FAN_SPEED 255   // Insert Value between 0 and 255
 
 //LCD and SD support
-//#define ULTRA_LCD  //general lcd support, also 16x2
+//#define ULTRA_LCD  //general LCD support, also 16x2
 //#define DOGLCD  // Support for SPI LCD 128x64 (Controller ST7565R graphic Display Family)
 //#define SDSUPPORT // Enable SD Card Support in Hardware Console
 //#define SDSLOW // Use slower SD transfer mode (not normally needed - uncomment if you're getting volume init error)
 //#define ENCODER_PULSES_PER_STEP 1 // Increase if you have a high resolution encoder
 //#define ENCODER_STEPS_PER_MENU_ITEM 5 // Set according to ENCODER_PULSES_PER_STEP or your liking
-//#define ULTIMAKERCONTROLLER //as available from the ultimaker online store.
-//#define ULTIPANEL  //the ultipanel as on thingiverse
+//#define ULTIMAKERCONTROLLER //as available from the Ultimaker online store.
+//#define ULTIPANEL  //the UltiPanel as on Thingiverse
 //#define LCD_FEEDBACK_FREQUENCY_HZ 1000	// this is the tone frequency the buzzer plays when on UI feedback. ie Screen Click
 //#define LCD_FEEDBACK_FREQUENCY_DURATION_MS 100 // the duration the buzzer plays the UI feedback sound. ie Screen Click
 
 // https://bitbucket.org/fmalpartida/new-liquidcrystal/wiki/schematics#!shiftregister-connection
 //#define SR_LCD
 #ifdef SR_LCD
-   #define SR_LCD_2W_NL    // Non latching 2 wire shiftregister
+   #define SR_LCD_2W_NL    // Non latching 2 wire shift register
    //#define NEWPANEL
 #endif
 
     #define LCD_WIDTH 20
     #define LCD_HEIGHT 4
   #endif
-#else //no panel but just lcd
+#else //no panel but just LCD
   #ifdef ULTRA_LCD
   #ifdef DOGLCD // Change number of lines to match the 128x64 graphics display
     #define LCD_WIDTH 20
 // Increase the FAN pwm frequency. Removes the PWM noise but increases heating in the FET/Arduino
 //#define FAST_PWM_FAN
 
-// Temperature status leds that display the hotend and bet temperature.
-// If alle hotends and bed temperature and temperature setpoint are < 54C then the BLUE led is on.
+// Temperature status LEDs that display the hotend and bet temperature.
+// If all hotends and bed temperature and temperature setpoint are < 54C then the BLUE led is on.
 // Otherwise the RED led is on. There is 1C hysteresis.
 //#define TEMP_STAT_LEDS
 

Marlin/Configuration_adv.h

 #define BED_CHECK_INTERVAL 5000 //ms between checks in bang-bang control
 
 //// Heating sanity check:
-// This waits for the watchperiod in milliseconds whenever an M104 or M109 increases the target temperature
+// This waits for the watch period in milliseconds whenever an M104 or M109 increases the target temperature
 // If the temperature has not increased at the end of that period, the target temperature is set to zero.
 // It can be reset with another M104/M109. This check is also only triggered if the target temperature and the current temperature
 //  differ by at least 2x WATCH_TEMP_INCREASE
 //#define WATCH_TEMP_INCREASE 10  //Heat up at least 10 degree in 20 seconds
 
 #ifdef PIDTEMP
-  // this adds an experimental additional term to the heatingpower, proportional to the extrusion speed.
-  // if Kc is choosen well, the additional required power due to increased melting should be compensated.
+  // this adds an experimental additional term to the heating power, proportional to the extrusion speed.
+  // if Kc is chosen well, the additional required power due to increased melting should be compensated.
   #define PID_ADD_EXTRUSION_RATE
   #ifdef PID_ADD_EXTRUSION_RATE
-    #define  DEFAULT_Kc (1) //heatingpower=Kc*(e_speed)
+    #define  DEFAULT_Kc (1) //heating power=Kc*(e_speed)
   #endif
 #endif
 
 // the target temperature is set to mintemp+factor*se[steps/sec] and limited by mintemp and maxtemp
 // you exit the value by any M109 without F*
 // Also, if the temperature is set to a value <mintemp, it is not changed by autotemp.
-// on an ultimaker, some initial testing worked with M109 S215 B260 F1 in the start.gcode
+// on an Ultimaker, some initial testing worked with M109 S215 B260 F1 in the start.gcode
 #define AUTOTEMP
 #ifdef AUTOTEMP
   #define AUTOTEMP_OLDWEIGHT 0.98
 #define SD_FINISHED_STEPPERRELEASE true  //if sd support and the file is finished: disable steppers?
 #define SD_FINISHED_RELEASECOMMAND "M84 X Y Z E" // You might want to keep the z enabled so your bed stays in place.
 
-#define SDCARD_RATHERRECENTFIRST  //reverse file order of sd card menu display. Its sorted practically after the filesystem block order.
-// if a file is deleted, it frees a block. hence, the order is not purely cronological. To still have auto0.g accessible, there is again the option to do that.
+#define SDCARD_RATHERRECENTFIRST  //reverse file order of sd card menu display. Its sorted practically after the file system block order.
+// if a file is deleted, it frees a block. hence, the order is not purely chronological. To still have auto0.g accessible, there is again the option to do that.
 // using:
 //#define MENU_ADDAUTOSTART
 
-// The hardware watchdog should reset the Microcontroller disabling all outputs, in case the firmware gets stuck and doesn't do temperature regulation.
+// The hardware watchdog should reset the microcontroller disabling all outputs, in case the firmware gets stuck and doesn't do temperature regulation.
 //#define USE_WATCHDOG
 
 #ifdef USE_WATCHDOG
 //#define ABORT_ON_ENDSTOP_HIT_FEATURE_ENABLED
 
 // Babystepping enables the user to control the axis in tiny amounts, independently from the normal printing process
-// it can e.g. be used to change z-positions in the print startup phase in realtime
+// it can e.g. be used to change z-positions in the print startup phase in real-time
 // does not respect endstops!
 //#define BABYSTEPPING
 #ifdef BABYSTEPPING
 //
 // advance (steps) = STEPS_PER_CUBIC_MM_E * EXTUDER_ADVANCE_K * cubic mm per second ^ 2
 //
-// hooke's law says:		force = k * distance
-// bernoulli's priniciple says:	v ^ 2 / 2 + g . h + pressure / density = constant
+// Hooke's law says:		force = k * distance
+// Bernoulli's principle says:	v ^ 2 / 2 + g . h + pressure / density = constant
 // so: v ^ 2 is proportional to number of steps we advance the extruder
 //#define ADVANCE
 
 //===========================================================================
 
 // The number of linear motions that can be in the plan at any give time.
-// THE BLOCK_BUFFER_SIZE NEEDS TO BE A POWER OF 2, i.g. 8,16,32 because shifts and ors are used to do the ringbuffering.
+// THE BLOCK_BUFFER_SIZE NEEDS TO BE A POWER OF 2, i.g. 8,16,32 because shifts and ors are used to do the ring-buffering.
 #if defined SDSUPPORT
   #define BLOCK_BUFFER_SIZE 16   // SD,LCD,Buttons take more memory, block buffer needs to be smaller
 #else
 #endif
 
 
-//The ASCII buffer for recieving from the serial:
+//The ASCII buffer for receiving from the serial:
 #define MAX_CMD_SIZE 96
 #define BUFSIZE 4
 
 
-// Firmware based and LCD controled retract
+// Firmware based and LCD controlled retract
 // M207 and M208 can be used to define parameters for the retraction.
 // The retraction can be called by the slicer using G10 and G11
 // until then, intended retractions can be detected by moves that only extrude and the direction.