README.md in self_data-0.1.1 vs README.md in self_data-1.0.0

@@ -1,50 +1,100 @@
 # SelfData
+
+It's like native ruby DATA but you can use it not only for main file.
+
+For example:
+```ruby
+# main.rb
+
+require 'self_data'
+require './a.rb'
+
+puts "DATA: #{A.native_data}"
+puts "SelfData: #{A.self_data}"
+
+__END__
+main.rb data
+```
+
+```ruby
+# a.rb
+
+module A
+  module_function
+
+  def native_data
+    DATA.read
+  end
+
+  def self_data
+    SelfData.read
+  end
+end
+
+__END__
+a.rb data
+```
+
+and if you execute it, you'll get:
+```
+$ ruby main.rb
+DATA: main.rb data
+SelfData: a.rb data
+```
+
+# Usage
+Use `SelfData.read()` to get text or use `SelfData.load(*formats, **options)` to get formatted data (like yaml, xml, erb, etc).
+
+Look at the [lib/self_data/config.rb](https://github.com/umbrellio/self_data/blob/master/lib/self_data/config.rb) for more details.
+
+# Note
+SelfData use caller, it's not fast, that is why you shouldn't use SelfData in loops.