what is parser in xml

I want to know what is parser in Xml ?.Is it remove tags from a html file as we use stringtokenizer to remove . / from urls.
I only know that we can make our own tags and can define thier properties/data types .
How I should relate basic xml with java.
Is java and xml by brett mclaughlin is for beginners ?

jaideep

An XML parser is a piece of software which helps your program to understand XML. The parser reads the text form of an XML document into some internal form, directly accessible by your Java code. For more details about the types of parsers, see the following post: http://www.javaranch.com/ubb/Forum31/HTML/000077.html
I know that "Java and XML" by Brett McLaughlin has received some good reviews, although I haven't read it myself. I think it should be helpful if you are a beginner at XML, but does require some Java knowledge.

There are two types of documents in XML.
1. well-formed (follows specific set of rules)
2. valid(if the document matches the constraints listed in DTD)
NOW.....
An XML parser reads the document and verifies that it is well formed. It also converts the document into a tree of elements.
Hope this helps....