SAX provides a streaming interface in which applications get the infoset from XML documents in a linear and continuous stream. Previously accessed data cannot be reread, because SAX is unidirectional and does not allow for backtracking. SAX conducts a search of large documents to fetch small pieces of information. It also provides a mechanism to abort the process once the information is located. SAX is a simpler and faster interface than the document object model (DOM).

The benefits of using SAX are as follows:

• SAX consumes less memory, as it collects the information from the document as a single stream. Therefore, the entire document does not need to be loaded into memory at once, allowing SAX to parse a file of any size.
• SAX has the advantage of fetching a small subset of information from a large document and is able to ignore unnecessary data.
• SAX makes it possible to get the required piece of information from a document as rapidly as possible.

Although there are many benefits to adopting SAX technology, it has its own set of drawbacks:

• It does not support random access to the document. (It can be difficult to use SAX on documents that contain many internal cross-references.)
• It does not provide lexical information. It is read-only.

SAX was initially developed as a joint effort by the members of the XML-DEV mailing list. The SAX project was recently shifted to the SourceForge project infrastructure. This was done to continue the further development and maintenance of SAX.