fix typos

correcting some spelling mistakes.

Author: Haitam-Elgharras

README.md

@@ -138,7 +138,7 @@ If the HTML referenced a resource on a different domain than www.google.com, the
 **Gotcha:**
 * The trailing slash in the URL “[http://facebook.com/](http://facebook.com/)” is important. In this case, the browser can safely add the slash. For URLs of the form http://example.com/folderOrFile, the browser cannot automatically add a slash, because it is not clear whether folderOrFile is a folder or a file. In such cases, the browser will visit the URL without the slash, and the server will respond with a redirect, resulting in an unnecessary roundtrip.
 * The server might respond with a 301 Moved Permanently response to tell the browser to go to “[http://www.google.com/](http://www.google.com/)” instead of “[http://google.com/](http://google.com/)”. There are interesting reasons why the server insists on the redirect instead of immediately responding with the web page that the user wants to see.
-One reason has to do with search engine rankings. See, if there are two URLs for the same page, say http://www.vasanth.com/ and http://vasanth.com/, search engine may consider them to be two different sites, each with fewer incoming links and thus a lower ranking. Search engines understand permanent redirects (301), and will combine the incoming links from both sources into a single ranking.
+One reason has to do with search engine rankings. See, if there are two URLs for the same page, say http://www.vasanth.com/ and http://vasanth.com/, search engines may consider them to be two different sites, each with fewer incoming links and thus a lower ranking. Search engines understand permanent redirects (301), and will combine the incoming links from both sources into a single ranking.
 Also, multiple URLs for the same content are not cache-friendly. When a piece of content has multiple names, it will potentially appear multiple times in caches.
 
 **Note:**
@@ -459,7 +459,7 @@ In the painting stage, the render tree is traversed and the renderer's "paint()"
 
 Like layout, painting can also be global–the entire tree is painted–or incremental. In incremental painting, some of the renderers change in a way that does not affect the entire tree. The changed renderer invalidates its rectangle on the screen. This causes the OS to see it as a "dirty region" and generate a "paint" event. The OS does it cleverly and coalesces several regions into one.
 
-Before repainting, WebKit saves the old rectangle as a bitmap. It then paints only the delta between the new and old rectangles. The browsers try to do the minimal possible actions in response to a change. So changes to an elements color will cause only repaint of the element. Changes to the element position will cause layout and repaint of the element, its children and possibly siblings. Adding a DOM node will cause layout and repaint of the node. Major changes, like increasing font size of the "html" element, will cause invalidation of caches, relayout and repaint of the entire tree.
+Before repainting, WebKit saves the old rectangle as a bitmap. It then paints only the delta between the new and old rectangles. The browsers try to do the minimal possible actions in response to a change. So changes to an element's color will cause only repaint of the element. Changes to the element position will cause layout and repaint of the element, its children and possibly siblings. Adding a DOM node will cause layout and repaint of the node. Major changes, like increasing font size of the "html" element, will cause invalidation of caches, relayout and repaint of the entire tree.
 
 There are three different positioning schemes:
 
@@ -486,7 +486,7 @@ Tim Berners-Lee, a British scientist at CERN, invented the World Wide Web (WWW)
 
 The first website at CERN - and in the world - was dedicated to the World Wide Web project itself and was hosted on Berners-Lee's NeXT computer. The website described the basic features of the web; how to access other people's documents and how to set up your own server. The NeXT machine - the original web server - is still at CERN. As part of the project to restore [the first website](http://info.cern.ch/), in 2013 CERN reinstated the world's first website to its original address.
 
-On 30 April 1993 CERN put the World Wide Web software in the public domain. CERN made the next release available with an open license, as a more sure way to maximize its dissemination. Through these actions, making the software required to run a web server freely available, along with a [basic browser](http://line-mode.cern.ch/) and a library of code, the web was allowed to flourish.
+On 30 April 1993, CERN put the World Wide Web software in the public domain. CERN made the next release available with an open license, as a more sure way to maximize its dissemination. Through these actions, making the software required to run a web server freely available, along with a [basic browser](http://line-mode.cern.ch/) and a library of code, the web was allowed to flourish.
 
 *More reading:*