Edits: spelling and grammar

manuscript/chapter1.md

@@ -1,8 +1,8 @@
 # React Application Setup: create-react-app
 
-You are going to implement a whole authentication mechanism in React with sign up, sign in and sign out. Furthermore, it should be possible to reset a password or change a password as a user. The latter option is only available for an authenticated user. Last but not least, it should be possible to protect certain routes (URLs) to be only used by authenticated users. Therefore you will build a proper authorization solution around it.
+You are going to implement a whole authentication mechanism in React with sign up, sign in and sign out. Furthermore, it should be possible to reset a password or change a password as a user. The latter option is only available for an authenticated user. Last, but not least, it should be possible to protect certain routes (URLs) to be accessible by authenticated users only. Therefore you will build a proper authorization solution around it.
 
-The application will be bootstrapped with Facebook's official React boilerplate project [create-react-app](https://github.com/facebookincubator/create-react-app). You can install it once globally on the command line and make use of it whenever you want afterward.
+The application will be bootstrapped with Facebook's official React boilerplate project [create-react-app](https://github.com/facebookincubator/create-react-app). You can install it once globally on the command line, and make use of it whenever you want afterward.
 
 {title="Command Line",lang="text"}
 ~~~~~~~~
@@ -17,7 +17,7 @@ create-react-app react-firebase-authentication
 cd react-firebase-authentication
 ~~~~~~~~
 
-Now you have the following commands on your command line to start and test your application. Unfortunately the tutorial doesn't cover testing yet.
+Now you have the following commands on your command line to start and test your application. Unfortunately, the tutorial doesn't cover testing yet.
 
 {title="Command Line",lang="text"}
 ~~~~~~~~
@@ -40,7 +40,7 @@ cd src
 mkdir components
 ~~~~~~~~
 
-Next, move the App component and all its related files to the *components/* folder. That way, you will start off with a well structured folder/file hierarchy.
+Next, move the App component and all its related files to the *components/* folder. That way, you will start off with a well-structured folder/file hierarchy.
 
 {title="Command Line",lang="text"}
 ~~~~~~~~
@@ -50,7 +50,7 @@ mv App.css components/
 mv logo.svg components/
 ~~~~~~~~
 
-Last but not least, fix the relative path to the App component in the *src/index.js* file. Since you have moved the App component, you need to add the */components* subpath.
+Last, but not least, fix the relative path to the App component in the *src/index.js* file. Since you have moved the App component, you need to add the */components* subpath.
 
 {title="src/index.js",lang=javascript}
 ~~~~~~~~
@@ -68,4 +68,4 @@ registerServiceWorker();
 
 Next, run your application on the command line again. It should work again and be accessible in the browser for you. Make yourself familiar with it if you haven't used create-react-app before.
 
-Before implementing the authentication in React, it would be great to have a couple of pages (e.g. sign up page, sign in page) to split up the application on multiple URLs (routes). Therefore, let's implement the routing with React Router first before diving into Firebase and the authentication afterward.
+Before implementing the authentication in React, it would be great to have a couple of pages (e.g. sign-up page, sign-in page) to split up the application into multiple URLs (routes). Therefore, let's implement the routing with React Router first before diving into Firebase and the authentication afterward.

manuscript/chapter2.md

@@ -1,6 +1,6 @@
 # React Router and Routes
 
-The following application should have multiple routes for the authentication mechanism but also for the application domain itself. Therefore, you can create a file to consolidate all the routes of your application in well defined constants. Keep it in a constants folder to add more of those files eventually.
+The following application should have multiple routes for the authentication mechanism but also for the application domain itself. Therefore, you can create a file to consolidate all the routes of your application in well-defined constants. Keep it in a constants folder to add more of those files eventually.
 
 {title="Command Line: src/",lang="text"}
 ~~~~~~~~
@@ -21,25 +21,25 @@ export const ACCOUNT = '/account';
 export const PASSWORD_FORGET = '/pw-forget';
 ~~~~~~~~
 
-Each route represents a page in your application. For instance, the sign up page should be reachable in development mode via *http://localhost:3000/signup* and in production mode via *http://yourdomain/signup*. Let's walk through the routes step by step.
+Each route represents a page in your application. For instance, the sign-up page should be reachable in development mode via *http://localhost:3000/signup* and in production mode via *http://yourdomain/signup*. Let's walk through the routes step by step.
 
-First of all, you will have a **sign up page** and a **sign in page**. You can take any web application out there as the blueprint to structure these routes for an authentication mechanism. For instance, take the following scenario: A user visits your web application. The user is convinced by your service and finds the button in the navigation bar to sign in to your application. But the user has no account yet, so a sign up button is presented as an alternative on the sign in page.
+First of all, you will have a **sign-up page** and a **sign-in page**. You can take any web application out there as the blueprint to structure these routes for an authentication mechanism. For instance, take the following scenario: A user visits your web application. The user is convinced by your service and finds the button in the navigation bar to sign in to your application. But the user has no account yet, so a sign-up button is presented as an alternative on the sign-in page.
 
 ![Sign In](images/sign.jpg)
 
-Second, there will be a **landing page** and a **home page**. The landing page is your root route. That's the place where a user ends up when visiting your web application by default. The user doesn't need to be authenticated to visit this route. On the other hand, the home page is a so called **protected route**. The user can only access it when being authenticated. You will implement the protection of the route by using authorization in this tutorial.
+Second, there will be a **landing page** and a **home page**. The landing page is your root route. That's the place where a user ends up when visiting your web application by default. The user doesn't need to be authenticated to visit this route. On the other hand, the home page is a so-called **protected route**. The user can only access it when being authenticated. You will implement the protection of the route by using authorization in this tutorial.
 
-Third, there will be a protected **account page** as well. On this page, a user can reset a password or change a password. It is secured by authorization as well and thus only reachable for authenticated.
+Third, there will be a protected **account page** as well. On this page, a user can reset a password or change a password. It is secured by authorization as well, and thus only reachable for authenticated.
 
 ![Account Page](images/account.jpg)
 
-Last but not least, the password forget component will be exposed on another non protected page, a **password forget page**, as well. It is used for users who are not authenticated and forgot about their password.
+Last, but not least, the password forget component will be exposed on another non-protected page, a **password-forget page**, as well. It is used for users who are not authenticated and forgot about their password.
 
 ![Password Forget Page](images/password-reset.jpg)
 
-Now all of these routes need to be accessible to the user. How to get started with the routing in React? The best way to start is implementing a Navigation component which is used in the App component. The App component is the perfect place to render the Navigation component, because it will always render the Navigation component but replace the other components (pages) based on the mapped route. Basically, the App component is the container where all your fixed components are going (navigation bar, side bar, footer) but also your components which are displayed depending on the route in the URL.
+Now, all of these routes need to be accessible to the user. How to get started with the routing in React? The best way to start is by implementing a Navigation component which is used in the App component. The App component is the perfect place to render the Navigation component, because it will always render the Navigation component but replace the other components (pages) based on the mapped route. Basically, the App component is the container where all your fixed components are going (navigation bar, side bar, footer) but also your components which are displayed depending on the route in the URL.
 
-First, refactor your App component to the following implementation. It will use the Navigation component and wraps it already in the Router component provided by React Router. The Router makes it possible to navigate from URL to URL on the client-side application without making requests to a webserver. Thus the applications need to be requested only once from the server and do the routing only on the client-side.
+First, refactor your App component as follows: It will use the Navigation component and wraps it already in the Router component provided by React Router. The Router makes it possible to navigate from URL-to-URL on the client-side application, without making requests to a web server. Thus, applications need to be requested only once from the server, with the process of handling requested routes handled on the client side.
 
 {title="src/components/App.js",lang=javascript}
 ~~~~~~~~
@@ -56,7 +56,7 @@ const App = () =>
 export default App;
 ~~~~~~~~
 
-In addition, you can remove the *logo.svg* because it isn't used anymore. Moreover, it is up to you to keep the *App.css* file to style your application in between of this tutorial.
+In addition, you can remove the *logo.svg* image, because it isn't used anymore. Moreover, it is up to you to keep the *App.css* file up to date, to enhance your application's appearance, as we proceed through this tutorial.
 
 {title="Command Line: src/components/",lang="text"}
 ~~~~~~~~
@@ -92,7 +92,7 @@ const Navigation = () =>
 export default Navigation;
 ~~~~~~~~
 
-Now, run your application again and verify two things: The links need to show up in your browser and once you click a link the URL has to change. However, even though the URL changes, the displayed content doesn't change. Let's implement this behavior.
+Now, run your application again and verify two things: The links need to show up in your browser; and once you click a link, the URL has to change. However, notice that even though the URL changes, the displayed content doesn't change. Let's implement this behavior.
 
 In your App component, you can specify which components should show up according to corresponding routes with the help of the Route component from React Router.
 
@@ -168,7 +168,7 @@ So if a route matches a path, the respective component will be displayed. Thus a
 touch Landing.js Home.js Account.js SignUp.js SignIn.js SignOut.js PasswordForget.js PasswordChange.js
 ~~~~~~~~
 
-In each component, define a simple boilerplate component as functional stateless component. That's sufficient for now. These components will be filled with business logic later on. For instance, the component for the Landing page could be defined as follows.
+In each component, define a simple boilerplate component as a functional, stateless component. That's sufficient for now. These components will be filled with business logic later on. For instance, the component for the Landing page could be defined as follows.
 
 {title="src/components/Landing.js",lang=javascript}
 ~~~~~~~~