README.md in hilbert-0.0.2700210 vs README.md in hilbert-0.0.2700300

@@ -1,14 +1,14 @@
 # Hilbert
 
 [![Gem Version](https://badge.fury.io/rb/hilbert.svg)](http://badge.fury.io/rb/hilbert) [![Build Status](https://travis-ci.org/gogotanaka/Hilbert.svg?branch=master)](https://travis-ci.org/gogotanaka/Hilbert) [![Coverage Status](https://coveralls.io/repos/gogotanaka/Hilbert/badge.png?branch=master)](https://coveralls.io/r/gogotanaka/Hilbert?branch=master) [![Code Climate](https://codeclimate.com/github/gogotanaka/Hilbert/badges/gpa.svg)](https://codeclimate.com/github/gogotanaka/Hilbert) [![Dependency Status](https://gemnasium.com/gogotanaka/Hilbert.svg)](https://gemnasium.com/gogotanaka/Hilbert)
 
-## Do you know the one best language in this world?
+### Do you know the one best language in this world?
 
-#### I believe mathematics(logic) is absolutely that one.
+#### I believe mathematics (logic) is absolutely that language.
 
-## How can we deal something as great as mathematics in a discrete world?
+### How can we deal something as great as mathematics in a discrete world?
 
 #### Hilbert is the answer.
 
 Hilbert lets you have a sense of mathematics using a keyboard, the same as you would with a pen.
 
@@ -20,25 +20,23 @@
 +--------------------+                    +------------------------+
 ```
 
 ## Demo
 
-The code below is input and output for the Hilbert interpreter
+The code below is input and output for the Hilbert interpreter. (You can try it with `hilbert -i`.)
 
-(you can try it by `hilbert -i`)
-
 ### Logic
 ```coffeescript
 P -> Q 
 Q -> R
 (P -> R)?
 => TRUE
 
 P | Q # P or Q
 ~P    # not P
-Q?    # Q is TURE?
-=> TURE
+Q?    # Q is TRUE?
+=> TRUE
 ```
 
 ### Differentiate
 
 ```
@@ -107,14 +105,16 @@
 ```
 
 
 ## How to use
 
-Install hilbert gem.
+Install the `hilbert` gem.
 
     $ gem install hilbert
 
+Note to OS X Users: If the above `gem` command does not work with the stock version of Ruby (due to not being able to build a target indicated in the Makefile), then you will need to install a version of Ruby that includes the appropriate header files. Using [homebrew](http://brew.sh/) (`brew install ruby`) will suffice.
+
 ## Interpreter
 
     $ hilbert -i
     Enjoy! ->
 
@@ -166,8 +166,8 @@
 end
 ```
 
 ## Contributing
 
-Any PRs or issues are welcome. (Please make to `develop` branch)
+Any PRs or issues are welcome. (Please make them to [the `develop` branch](https://github.com/gogotanaka/Hilbert/tree/develop).)
 
-You can become a commiter, even if you only commit once.
+You can become a committer, even if you only commit once.