What is SAX in XML?

SAX stands for Simple API for XML. It is a sequential access parser. It is a simple API for XML which provides a mechanism for reading data from an XML document. It is an alternative of DOM. DOM operates on the documents as whole, SAX parsers operate on each piece of the XML document sequentially.

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SAX has no formal specification like DOM and consumes less memory. But it can be used to read the XML document only not write.