diff --git a/Libraries/Animated/src/__tests__/bezier-test.js b/Libraries/Animated/src/__tests__/bezier-test.js
index e34c4f799..3f1070a48 100644
--- a/Libraries/Animated/src/__tests__/bezier-test.js
+++ b/Libraries/Animated/src/__tests__/bezier-test.js
@@ -121,7 +121,7 @@ describe('bezier', function() {
         assertClose(easing(0.5), 0.5, 2);
       });
     });
-    it('should be symetrical', function() {
+    it('should be symmetrical', function() {
       repeat(10)(function() {
         var a = Math.random(),
           b = 2 * Math.random() - 0.5,
diff --git a/Libraries/Animated/src/createAnimatedComponent.js b/Libraries/Animated/src/createAnimatedComponent.js
index 7126deaf2..2e10a6c71 100644
--- a/Libraries/Animated/src/createAnimatedComponent.js
+++ b/Libraries/Animated/src/createAnimatedComponent.js
@@ -149,7 +149,7 @@ function createAnimatedComponent(Component: any): any {
           ref={this._setComponentRef}
           // The native driver updates views directly through the UI thread so we
           // have to make sure the view doesn't get optimized away because it cannot
-          // go through the NativeViewHierachyManager since it operates on the shadow
+          // go through the NativeViewHierarchyManager since it operates on the shadow
           // thread.
           collapsable={
             this._propsAnimated.__isNative ? false : props.collapsable
diff --git a/Libraries/Animated/src/nodes/AnimatedInterpolation.js b/Libraries/Animated/src/nodes/AnimatedInterpolation.js
index cfe9e701e..141929e5b 100644
--- a/Libraries/Animated/src/nodes/AnimatedInterpolation.js
+++ b/Libraries/Animated/src/nodes/AnimatedInterpolation.js
@@ -374,7 +374,7 @@ class AnimatedInterpolation extends AnimatedWithChildren {
 
     return {
       inputRange: this._config.inputRange,
-      // Only the `outputRange` can contain strings so we don't need to tranform `inputRange` here
+      // Only the `outputRange` can contain strings so we don't need to transform `inputRange` here
       outputRange: this.__transformDataType(this._config.outputRange),
       extrapolateLeft:
         this._config.extrapolateLeft || this._config.extrapolate || 'extend',
diff --git a/Libraries/Animated/src/nodes/AnimatedValueXY.js b/Libraries/Animated/src/nodes/AnimatedValueXY.js
index 496ccd795..4df709729 100644
--- a/Libraries/Animated/src/nodes/AnimatedValueXY.js
+++ b/Libraries/Animated/src/nodes/AnimatedValueXY.js
@@ -43,7 +43,7 @@ class AnimatedValueXY extends AnimatedWithChildren {
     } else {
       invariant(
         value.x instanceof AnimatedValue && value.y instanceof AnimatedValue,
-        'AnimatedValueXY must be initalized with an object of numbers or ' +
+        'AnimatedValueXY must be initialized with an object of numbers or ' +
           'AnimatedValues.',
       );
       this.x = value.x;
diff --git a/Libraries/BatchedBridge/BatchedBridge.js b/Libraries/BatchedBridge/BatchedBridge.js
index f3e735f48..46e8b5f41 100644
--- a/Libraries/BatchedBridge/BatchedBridge.js
+++ b/Libraries/BatchedBridge/BatchedBridge.js
@@ -18,7 +18,7 @@ const MessageQueue = require('MessageQueue');
 // This makes stacktraces to be placed at MessageQueue rather than at where they were launched
 // The parameter __fbUninstallRNGlobalErrorHandler is passed to MessageQueue to prevent the handler from being installed
 //
-// __fbUninstallRNGlobalErrorHandler is conditionally set by the Inspector while the VM is paused for intialization
+// __fbUninstallRNGlobalErrorHandler is conditionally set by the Inspector while the VM is paused for initialization
 // If the Inspector isn't present it defaults to undefined and the global error handler is installed
 // The Inspector can still call MessageQueue#uninstallGlobalErrorHandler to uninstalled on attach
 
diff --git a/Libraries/Components/Navigation/NavigatorIOS.ios.js b/Libraries/Components/Navigation/NavigatorIOS.ios.js
index 96bdd3629..fe90fb9f6 100644
--- a/Libraries/Components/Navigation/NavigatorIOS.ios.js
+++ b/Libraries/Components/Navigation/NavigatorIOS.ios.js
@@ -337,7 +337,7 @@ var NavigatorIOS = createReactClass({
       /**
        * Use this to specify additional props to pass to the rendered
        * component. `NavigatorIOS` will automatically pass in `route` and
-       * `navigator` props to the comoponent.
+       * `navigator` props to the component.
        */
       passProps: PropTypes.object,
 
diff --git a/Libraries/Components/ScrollView/ScrollViewStickyHeader.js b/Libraries/Components/ScrollView/ScrollViewStickyHeader.js
index e86f724ba..0a320e0e3 100644
--- a/Libraries/Components/ScrollView/ScrollViewStickyHeader.js
+++ b/Libraries/Components/ScrollView/ScrollViewStickyHeader.js
@@ -71,7 +71,7 @@ class ScrollViewStickyHeader extends React.Component<Props, {
       // - Past the collision with the next header y: no more translation. This will cause the
       // header to continue scrolling up and make room for the next sticky header.
       // In the case that there is no next header just translate equally to
-      // scroll indefinetly.
+      // scroll indefinitely.
       inputRange.push(layoutY);
       outputRange.push(0);
       // Sometimes headers jump around so we make sure we don't violate the monotonic inputRange
diff --git a/Libraries/Components/StatusBar/StatusBar.js b/Libraries/Components/StatusBar/StatusBar.js
index 9cbe6e406..c545b3810 100644
--- a/Libraries/Components/StatusBar/StatusBar.js
+++ b/Libraries/Components/StatusBar/StatusBar.js
@@ -315,7 +315,7 @@ class StatusBar extends React.Component<{
     // Every time a StatusBar component is mounted, we push it's prop to a stack
     // and always update the native status bar with the props from the top of then
     // stack. This allows having multiple StatusBar components and the one that is
-    // added last or is deeper in the view hierachy will have priority.
+    // added last or is deeper in the view hierarchy will have priority.
     this._stackEntry = createStackEntry(this.props);
     StatusBar._propsStack.push(this._stackEntry);
     this._updatePropsStack();
diff --git a/Libraries/Experimental/Incremental.js b/Libraries/Experimental/Incremental.js
index ec08ea97d..eb9d9a842 100644
--- a/Libraries/Experimental/Incremental.js
+++ b/Libraries/Experimental/Incremental.js
@@ -32,7 +32,7 @@ const DEBUG = false;
  *
  * `<Incremental>` solves this by slicing up rendering into chunks that are
  * spread across multiple event loops. Expensive components can be sliced up
- * recursively by wrapping pieces of them and their decendents in
+ * recursively by wrapping pieces of them and their descendants in
  * `<Incremental>` components. `<IncrementalGroup>` can be used to make sure
  * everything in the group is rendered recursively before calling `onDone` and
  * moving on to another sibling group (e.g. render one row at a time, even if
@@ -83,7 +83,7 @@ const DEBUG = false;
  */
 export type Props = {
  /**
-  * Called when all the decendents have finished rendering and mounting
+  * Called when all the descendants have finished rendering and mounting
   * recursively.
   */
  onDone?: () => void,
diff --git a/Libraries/Experimental/IncrementalPresenter.js b/Libraries/Experimental/IncrementalPresenter.js
index 4dc10074e..8f273974c 100644
--- a/Libraries/Experimental/IncrementalPresenter.js
+++ b/Libraries/Experimental/IncrementalPresenter.js
@@ -27,7 +27,7 @@ import type {Context} from 'Incremental';
  *
  * `<IncrementalPresenter>` can be used to group sets of `<Incremental>` renders
  * such that they are initially invisible and removed from layout until all
- * decendents have finished rendering, at which point they are drawn all at once
+ * descendants have finished rendering, at which point they are drawn all at once
  * so the UI doesn't jump around during the incremental rendering process.
  *
  * See Incremental.js for more info.
diff --git a/Libraries/Experimental/SwipeableRow/SwipeableFlatList.js b/Libraries/Experimental/SwipeableRow/SwipeableFlatList.js
index 3020047bf..6aa7c253a 100644
--- a/Libraries/Experimental/SwipeableRow/SwipeableFlatList.js
+++ b/Libraries/Experimental/SwipeableRow/SwipeableFlatList.js
@@ -51,7 +51,7 @@ type State = {
  *
  * - It ensures that at most 1 row is swiped open (auto closes others)
  * - It can bounce the 1st row of the list so users know it's swipeable
- * - Increase performance on iOS by locking list swiping when row swiping is occuring
+ * - Increase performance on iOS by locking list swiping when row swiping is occurring
  * - More to come
  */
 
diff --git a/Libraries/Experimental/WindowedListView.js b/Libraries/Experimental/WindowedListView.js
index 9d0e0ac9a..08bf44d6d 100644
--- a/Libraries/Experimental/WindowedListView.js
+++ b/Libraries/Experimental/WindowedListView.js
@@ -392,7 +392,7 @@ class WindowedListView extends React.Component<Props, State> {
     }
     if (props.onEndReached) {
       // Make sure we call onEndReached exactly once every time we reach the
-      // end.  Resets if scoll back up and down again.
+      // end.  Resets if scroll back up and down again.
       const willBeAtTheEnd = lastRow === (totalRows - 1);
       if (willBeAtTheEnd && !this._hasCalledOnEndReached) {
         props.onEndReached();
diff --git a/Libraries/Lists/SectionList.js b/Libraries/Lists/SectionList.js
index f547066f1..354d6c6a4 100644
--- a/Libraries/Lists/SectionList.js
+++ b/Libraries/Lists/SectionList.js
@@ -281,7 +281,7 @@ class SectionList<SectionT: SectionBase<any>> extends React.PureComponent<
   }
 
   /**
-   * Tells the list an interaction has occured, which should trigger viewability calculations, e.g.
+   * Tells the list an interaction has occurred, which should trigger viewability calculations, e.g.
    * if `waitForInteractions` is true and the user has not scrolled. This is typically called by
    * taps on items or by navigation actions.
    */
diff --git a/Libraries/Lists/VirtualizeUtils.js b/Libraries/Lists/VirtualizeUtils.js
index c43b13251..8845ed835 100644
--- a/Libraries/Lists/VirtualizeUtils.js
+++ b/Libraries/Lists/VirtualizeUtils.js
@@ -125,7 +125,7 @@ function computeWindowedRenderLimits(
     };
   }
 
-  // Find the indices that correspond to the items at the render boundaries we're targetting.
+  // Find the indices that correspond to the items at the render boundaries we're targeting.
   let [overscanFirst, first, last, overscanLast] = elementsThatOverlapOffsets(
     [overscanBegin, visibleBegin, visibleEnd, overscanEnd],
     props.getItemCount(props.data),
diff --git a/Libraries/NativeAnimation/Drivers/RCTFrameAnimation.m b/Libraries/NativeAnimation/Drivers/RCTFrameAnimation.m
index cd8b3a481..a46fea6bf 100644
--- a/Libraries/NativeAnimation/Drivers/RCTFrameAnimation.m
+++ b/Libraries/NativeAnimation/Drivers/RCTFrameAnimation.m
@@ -115,7 +115,7 @@ RCT_NOT_IMPLEMENTED(- (instancetype)init)
     return;
   }
 
-  // Do a linear remap of the two frames to safegaurd against variable framerates
+  // Do a linear remap of the two frames to safeguard against variable framerates
   NSNumber *fromFrameValue = _frames[startIndex];
   NSNumber *toFrameValue = _frames[nextIndex];
   NSTimeInterval fromInterval = startIndex * RCTSingleFrameInterval;
diff --git a/Libraries/Performance/SamplingProfiler.js b/Libraries/Performance/SamplingProfiler.js
index de8c2c0ac..87142782e 100644
--- a/Libraries/Performance/SamplingProfiler.js
+++ b/Libraries/Performance/SamplingProfiler.js
@@ -24,7 +24,7 @@ const SamplingProfiler = {
       }
     } catch (e) {
       console.log(
-        'Error occured when restarting Sampling Profiler: ' + e.toString());
+        'Error occurred when restarting Sampling Profiler: ' + e.toString());
       error = e.toString();
     }
 
diff --git a/Libraries/Text/TextInput/Multiline/RCTMultilineTextInputView.m b/Libraries/Text/TextInput/Multiline/RCTMultilineTextInputView.m
index a37738bad..dea7d888c 100644
--- a/Libraries/Text/TextInput/Multiline/RCTMultilineTextInputView.m
+++ b/Libraries/Text/TextInput/Multiline/RCTMultilineTextInputView.m
@@ -346,7 +346,7 @@ static BOOL findMismatch(NSString *first, NSString *second, NSRange *firstRange,
 {
   [self invalidateContentSize];
 
-  // Detect when _backedTextInput updates happend that didn't invoke `shouldChangeTextInRange`
+  // Detect when _backedTextInput updates happened that didn't invoke `shouldChangeTextInRange`
   // (e.g. typing simplified chinese in pinyin will insert and remove spaces without
   // calling shouldChangeTextInRange).  This will cause JS to get out of sync so we
   // update the mismatched range.
diff --git a/Libraries/polyfills/console.js b/Libraries/polyfills/console.js
index 747b0521e..0564491af 100644
--- a/Libraries/polyfills/console.js
+++ b/Libraries/polyfills/console.js
@@ -477,7 +477,7 @@ if (global.nativeLoggingHook) {
     });
 
     // Join all elements in the row into a single string with | separators
-    // (appends extra spaces to each cell to make separators  | alligned)
+    // (appends extra spaces to each cell to make separators  | aligned)
     function joinRow(row, space) {
       var cells = row.map(function(cell, i) {
         var extraSpaces = repeat(' ', columnWidths[i] - cell.length).join('');
diff --git a/Libraries/vendor/core/Map.js b/Libraries/vendor/core/Map.js
index 33f206fcc..7d7086571 100644
--- a/Libraries/vendor/core/Map.js
+++ b/Libraries/vendor/core/Map.js
@@ -436,7 +436,7 @@ module.exports = (function(global, undefined) {
     // property of our choosing that we associate with the object. Association
     // is done by ways of keeping a non-enumerable property on the object.
     // Ideally these would be `Object.create(null)` objects but since we're
-    // trying to support ES3 we'll have to gaurd against collisions using
+    // trying to support ES3 we'll have to guard against collisions using
     // prefixes on the keys rather than rely on null prototype objects.
     map._objectIndex = {};
 
diff --git a/Libraries/vendor/document/selection/DocumentSelectionState.js b/Libraries/vendor/document/selection/DocumentSelectionState.js
index 87ce63bce..fbfcc3062 100644
--- a/Libraries/vendor/document/selection/DocumentSelectionState.js
+++ b/Libraries/vendor/document/selection/DocumentSelectionState.js
@@ -20,7 +20,7 @@ var mixInEventEmitter = require('mixInEventEmitter');
  *
  * It is intended for use by AbstractTextEditor-based components for
  * identifying the appropriate start/end positions to modify the
- * DocumentContent, and for programatically setting browser selection when
+ * DocumentContent, and for programmatically setting browser selection when
  * components re-render.
  */
 class DocumentSelectionState {
diff --git a/RNTester/js/messagingtest.html b/RNTester/js/messagingtest.html
index c9258dbf5..31200b766 100644
--- a/RNTester/js/messagingtest.html
+++ b/RNTester/js/messagingtest.html
@@ -6,7 +6,7 @@
     <meta name="viewport" content="width=320, user-scalable=no">
   </head>
   <body>
-    <p>Messages recieved from React Native: 0</p>
+    <p>Messages received from React Native: 0</p>
     <p>(No messages)</p>
     <button type="button">
       Send message to React Native
@@ -17,7 +17,7 @@
     document.addEventListener('message', function(e) {
       messagesReceivedFromReactNative += 1;
       document.getElementsByTagName('p')[0].innerHTML =
-        'Messages recieved from React Native: ' + messagesReceivedFromReactNative;
+        'Messages received from React Native: ' + messagesReceivedFromReactNative;
       document.getElementsByTagName('p')[1].innerHTML = e.data;
     });
 
diff --git a/React/Base/RCTBridge.h b/React/Base/RCTBridge.h
index abf7225d2..4944ce711 100644
--- a/React/Base/RCTBridge.h
+++ b/React/Base/RCTBridge.h
@@ -32,7 +32,7 @@ RCT_EXTERN NSString *const RCTJavaScriptDidLoadNotification;
 
 /**
  * This notification fires when the bridge failed to load the JS bundle. The
- * `error` key can be used to determine the error that occured.
+ * `error` key can be used to determine the error that occurred.
  */
 RCT_EXTERN NSString *const RCTJavaScriptDidFailToLoadNotification;
 
@@ -220,7 +220,7 @@ RCT_EXTERN NSString *RCTBridgeModuleNameForClass(Class bridgeModuleClass);
 - (void)requestReload __deprecated_msg("Call reload instead");
 
 /**
- * Says whether bridge has started recieving calls from javascript.
+ * Says whether bridge has started receiving calls from javascript.
  */
 - (BOOL)isBatchActive;
 
diff --git a/React/Base/RCTEventDispatcher.m b/React/Base/RCTEventDispatcher.m
index 40a1d63a7..239da2665 100644
--- a/React/Base/RCTEventDispatcher.m
+++ b/React/Base/RCTEventDispatcher.m
@@ -207,7 +207,7 @@ RCT_EXPORT_MODULE()
   return RCTJSThread;
 }
 
-// js thread only (which suprisingly can be the main thread, depends on used JS executor)
+// js thread only (which surprisingly can be the main thread, depends on used JS executor)
 - (void)flushEventsQueue
 {
   [_eventQueueLock lock];
diff --git a/React/Base/RCTUtils.h b/React/Base/RCTUtils.h
index dcb2604a2..6a3e0c08d 100644
--- a/React/Base/RCTUtils.h
+++ b/React/Base/RCTUtils.h
@@ -30,7 +30,7 @@ RCT_EXTERN id RCTJSONClean(id object);
 RCT_EXTERN NSString *RCTMD5Hash(NSString *string);
 
 // Check if we are currently on the main queue (not to be confused with
-// the main thread, which is not neccesarily the same thing)
+// the main thread, which is not necessarily the same thing)
 // https://twitter.com/olebegemann/status/738656134731599872
 RCT_EXTERN BOOL RCTIsMainQueue(void);
 
diff --git a/React/Modules/RCTUIManager.m b/React/Modules/RCTUIManager.m
index a4d9bbb21..4b2dd504f 100644
--- a/React/Modules/RCTUIManager.m
+++ b/React/Modules/RCTUIManager.m
@@ -777,7 +777,7 @@ RCT_EXPORT_METHOD(removeSubviewsFromContainerWithID:(nonnull NSNumber *)containe
     NSUInteger originalIndex = [originalSuperview.subviews indexOfObjectIdenticalTo:removedChild];
     [container removeReactSubview:removedChild];
     // Disable user interaction while the view is animating
-    // since the view is (conseptually) deleted and not supposed to be interactive.
+    // since the view is (conceptually) deleted and not supposed to be interactive.
     removedChild.userInteractionEnabled = NO;
     [originalSuperview insertSubview:removedChild atIndex:originalIndex];
 
@@ -1150,7 +1150,7 @@ RCT_EXPORT_METHOD(dispatchViewManagerCommand:(nonnull NSNumber *)reactTag
 - (void)setNeedsLayout
 {
   // If there is an active batch layout will happen when batch finished, so we will wait for that.
-  // Otherwise we immidiately trigger layout.
+  // Otherwise we immediately trigger layout.
   if (![_bridge isBatchActive] && ![_bridge isLoading]) {
     [self _layoutAndMount];
   }
diff --git a/React/Views/RCTNavigator.m b/React/Views/RCTNavigator.m
index fdbdcab78..dbe48f796 100644
--- a/React/Views/RCTNavigator.m
+++ b/React/Views/RCTNavigator.m
@@ -47,7 +47,7 @@ NSInteger kNeverProgressed = -10000;
 
 @interface UINavigationController ()
 
-// need to declare this since `UINavigationController` doesnt publicly declare the fact that it implements
+// need to declare this since `UINavigationController` doesn't publicly declare the fact that it implements
 // UINavigationBarDelegate :(
 - (BOOL)navigationBar:(UINavigationBar *)navigationBar shouldPopItem:(UINavigationItem *)item;
 
diff --git a/React/Views/RCTShadowView.h b/React/Views/RCTShadowView.h
index db05a85a5..4020d3b0d 100644
--- a/React/Views/RCTShadowView.h
+++ b/React/Views/RCTShadowView.h
@@ -109,7 +109,7 @@ typedef void (^RCTApplierBlock)(NSDictionary<NSNumber *, UIView *> *viewRegistry
 
 /**
  * Convenient alias to `width` and `height` in pixels.
- * Defaults to NAN in case of non-pixel dimention.
+ * Defaults to NAN in case of non-pixel dimension.
  */
 @property (nonatomic, assign) CGSize size;
 
diff --git a/React/Views/RCTView.h b/React/Views/RCTView.h
index fd0071f93..992dc65c6 100644
--- a/React/Views/RCTView.h
+++ b/React/Views/RCTView.h
@@ -49,7 +49,7 @@
 /**
  * Layout direction of the view.
  * This is inherited from UIView+React, but we override it here
- * to improve perfomance and make subclassing/overriding possible/easier.
+ * to improve performance and make subclassing/overriding possible/easier.
  */
 @property (nonatomic, assign) UIUserInterfaceLayoutDirection reactLayoutDirection;
 
diff --git a/React/Views/ScrollView/RCTScrollContentShadowView.m b/React/Views/ScrollView/RCTScrollContentShadowView.m
index 7c0681112..700ab1813 100644
--- a/React/Views/ScrollView/RCTScrollContentShadowView.m
+++ b/React/Views/ScrollView/RCTScrollContentShadowView.m
@@ -36,7 +36,7 @@
 
   // Motivation:
   // Yoga place `contentView` on the right side of `scrollView` when RTL layout is enfoced.
-  // That breaks everything; it is completly pointless to (re)position `contentView`
+  // That breaks everything; it is completely pointless to (re)position `contentView`
   // because it is `contentView`'s job. So, we work around it here.
 
   // Step 1. Compensate `absolutePosition` change.
diff --git a/ReactAndroid/src/main/java/com/facebook/react/devsupport/DevSupportManagerImpl.java b/ReactAndroid/src/main/java/com/facebook/react/devsupport/DevSupportManagerImpl.java
index f529a4491..76c03be47 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/devsupport/DevSupportManagerImpl.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/devsupport/DevSupportManagerImpl.java
@@ -90,7 +90,7 @@ import okhttp3.RequestBody;
  * when app is backgrounded.
  *
  * {@link com.facebook.react.ReactInstanceManager} implementation is responsible for instantiating
- * this class as well as for populating with a referece to {@link CatalystInstance} whenever
+ * this class as well as for populating with a reference to {@link CatalystInstance} whenever
  * instance manager recreates it (through {@link #onNewReactContextCreated). Also, instance manager
  * is responsible for enabling/disabling dev support in case when app is backgrounded or when all
  * the views has been detached from the instance (through {@link #setDevSupportEnabled} method).
diff --git a/ReactAndroid/src/main/java/com/facebook/react/flat/FlatViewGroup.java b/ReactAndroid/src/main/java/com/facebook/react/flat/FlatViewGroup.java
index e10a02a6f..f46d6745b 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/flat/FlatViewGroup.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/flat/FlatViewGroup.java
@@ -119,7 +119,7 @@ import com.facebook.react.uimanager.ReactClippingViewGroup;
     }
 
     /**
-     * Propogates image load events to javascript if the hosting view is still alive.
+     * Propagates image load events to javascript if the hosting view is still alive.
      *
      * @param reactTag The view id.
      * @param imageLoadEvent The event type.
diff --git a/ReactAndroid/src/main/java/com/facebook/react/flat/RCTImageView.java b/ReactAndroid/src/main/java/com/facebook/react/flat/RCTImageView.java
index d06b1c4e0..fd4da4a3d 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/flat/RCTImageView.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/flat/RCTImageView.java
@@ -21,7 +21,7 @@ import com.facebook.react.views.image.ImageResizeMode;
 
 /**
  * RCTImageView is a top-level node for Image. It can display either a remote image
- * (source must start wtih http:// or https://) or a local resource (a BitmapDrawable).
+ * (source must start with http:// or https://) or a local resource (a BitmapDrawable).
  */
 /* package */ class RCTImageView<T extends AbstractDrawCommand & DrawImage> extends FlatShadowNode {
 
diff --git a/ReactAndroid/src/main/jni/first-party/fb/include/fb/fbjni/Registration-inl.h b/ReactAndroid/src/main/jni/first-party/fb/include/fb/fbjni/Registration-inl.h
index d387b5ef1..33da549c3 100644
--- a/ReactAndroid/src/main/jni/first-party/fb/include/fb/fbjni/Registration-inl.h
+++ b/ReactAndroid/src/main/jni/first-party/fb/include/fb/fbjni/Registration-inl.h
@@ -18,7 +18,7 @@ namespace jni {
 namespace detail {
 
 #ifdef __i386__
-// X86 ABI forces 16 byte stack allignment on calls. Unfortunately
+// X86 ABI forces 16 byte stack alignment on calls. Unfortunately
 // sometimes Dalvik chooses not to obey the ABI:
 // - https://code.google.com/p/android/issues/detail?id=61012
 // - https://android.googlesource.com/platform/ndk/+/81696d2%5E!/
diff --git a/ReactCommon/cxxreact/CxxNativeModule.cpp b/ReactCommon/cxxreact/CxxNativeModule.cpp
index a8e511fbe..4b71e3bef 100644
--- a/ReactCommon/cxxreact/CxxNativeModule.cpp
+++ b/ReactCommon/cxxreact/CxxNativeModule.cpp
@@ -110,7 +110,7 @@ void CxxNativeModule::invoke(unsigned int reactMethodId, folly::dynamic&& params
   params.resize(params.size() - method.callbacks);
 
   // I've got a few flawed options here.  I can let the C++ exception
-  // propogate, and the registry will log/convert them to java exceptions.
+  // propagate, and the registry will log/convert them to java exceptions.
   // This lets all the java and red box handling work ok, but the only info I
   // can capture about the C++ exception is the what() string, not the stack.
   // I can std::terminate() the app.  This causes the full, accurate C++
diff --git a/ReactCommon/cxxreact/ModuleRegistry.h b/ReactCommon/cxxreact/ModuleRegistry.h
index 0b55d9ce5..8df870e88 100644
--- a/ReactCommon/cxxreact/ModuleRegistry.h
+++ b/ReactCommon/cxxreact/ModuleRegistry.h
@@ -56,7 +56,7 @@ class RN_EXPORT ModuleRegistry {
   std::unordered_map<std::string, size_t> modulesByName_;
 
   // This is populated with modules that are requested via getConfig but are unknown.
-  // An error will be thrown if they are subsquently added to the registry.
+  // An error will be thrown if they are subsequently added to the registry.
   std::unordered_set<std::string> unknownModules_;
 
   // Function will be called if a module was requested but was not found.
diff --git a/ReactCommon/yoga/yoga/YGNode.h b/ReactCommon/yoga/yoga/YGNode.h
index ac81b3bb7..b90c0e336 100644
--- a/ReactCommon/yoga/yoga/YGNode.h
+++ b/ReactCommon/yoga/yoga/YGNode.h
@@ -65,9 +65,9 @@ struct YGNode {
   YGMeasureFunc getMeasure() const;
   YGBaselineFunc getBaseline() const;
   YGDirtiedFunc getDirtied() const;
-  // For Perfomance reasons passing as reference.
+  // For Performance reasons passing as reference.
   YGStyle& getStyle();
-  // For Perfomance reasons passing as reference.
+  // For Performance reasons passing as reference.
   YGLayout& getLayout();
   uint32_t getLineIndex() const;
   YGNodeRef getParent() const;
diff --git a/local-cli/core/makeCommand.js b/local-cli/core/makeCommand.js
index 901b2f864..2eab6caf1 100644
--- a/local-cli/core/makeCommand.js
+++ b/local-cli/core/makeCommand.js
@@ -26,7 +26,7 @@ module.exports = function makeCommand(command) {
 
     commandProcess.on('close', function prelink(code) {
       if (code) {
-        throw new Error(`Error occured during executing "${command}" command`);
+        throw new Error(`Error occurred during executing "${command}" command`);
       }
 
       cb();
diff --git a/local-cli/generator/copyProjectTemplateAndReplace.js b/local-cli/generator/copyProjectTemplateAndReplace.js
index a7deff596..91a392ee4 100644
--- a/local-cli/generator/copyProjectTemplateAndReplace.js
+++ b/local-cli/generator/copyProjectTemplateAndReplace.js
@@ -137,7 +137,7 @@ function upgradeFileContentChangedCallback(
   } else if (contentChanged === 'identical') {
     return 'keep';
   } else {
-    throw new Error(`Unkown file changed state: ${relativeDestPath}, ${contentChanged}`);
+    throw new Error(`Unknown file changed state: ${relativeDestPath}, ${contentChanged}`);
   }
 }
 
diff --git a/local-cli/link/ios/createGroup.js b/local-cli/link/ios/createGroup.js
index dac9ec66c..aba805d76 100644
--- a/local-cli/link/ios/createGroup.js
+++ b/local-cli/link/ios/createGroup.js
@@ -4,7 +4,7 @@ const hasGroup = (pbxGroup, name) => pbxGroup.children.find(group => group.comme
 
 /**
  * Given project and path of the group, it deeply creates a given group
- * making all outer groups if neccessary
+ * making all outer groups if necessary
  *
  * Returns newly created group
  */
diff --git a/local-cli/server/util/messageSocket.js b/local-cli/server/util/messageSocket.js
index 45aa68a20..d8b0236dd 100644
--- a/local-cli/server/util/messageSocket.js
+++ b/local-cli/server/util/messageSocket.js
@@ -144,7 +144,7 @@ function attachToServer(server, path) {
           });
           break;
         default:
-          throw `unkown method: ${message.method}`;
+          throw `unknown method: ${message.method}`;
       }
 
       clientWs.send(JSON.stringify({