Update README.md

README.md

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 The `goxpp` library is an XML parser library that is loosely based on the [Java XMLPullParser](http://www.xmlpull.org/v1/download/unpacked/doc/quick_intro.html).  This library allows you to easily parse arbitrary XML content using a pull parser.  You can think of `goxpp` as a lightweight wrapper around Go's XML `Decoder` that provides a set of functions that make it easier to parse XML content than using the raw decoder itself.
 
+## Overview
+
+To begin parsing a XML document using `goxpp` you must pass it an `io.Reader` object for your document:
+
+```go
+file, err := os.Open("path/file.xml")
+parser := xpp.NewXMLPullParser(file, false, charset.NewReader)
+```
+
+The `goxpp` library decodes documents into a series of token objects:
+
+| Token Name                       |
+|----------------------------------|
+| 	StartDocument                  |
+| 	EndDocument                    |
+| 	StartTag                       |
+| 	EndTag                         |
+| 	Text                           |
+| 	Comment                        |
+| 	ProcessingInstruction          |
+| 	Directive                      |
+| 	IgnorableWhitespace            |
+
+You will always start at the `StartDocument` token and can use the following functions to walk through a document:
+
+| Function Name                    | Description                           |
+|----------------------------------|---------------------------------------|
+| 	 Next()                        | Advance to the next `Text`, `StartTag`, `EndTag`, `EndDocument` token.<br>Note: skips `Comment`, `Directive` and `ProcessingInstruction` |
+| 	NextToken()                    | Advance to the next token regardless of type.                                                                |
+| 	NextText()                     | Advance to the next `Text` token.                                                                |
+| 	Skip()                         | Skip the next token.   |
+| 	DecodeElement(v interface{})   | Decode an entire element from the current tag into a struct.<br>Note: must be at a `StartTag` token |
+
+
+
 This project is licensed under the [MIT License](https://raw.githubusercontent.com/mmcdole/goxpp/master/LICENSE)