Section 2.9 XML
Extensible Markup Language (XML), is another human- and machine-readable language that is used frequently by web services and APIs. However, instead of being based on key-value pairs, XML relies on nodes, tags, and elements. The author defines these tags to specify what information is included in each element of the XML document and allows for elements to be nested within one another. The nodes define the hierarchical structure of the XML (which means that XML is hierarchical and nested like JSON)!
XML accomplishes the same goal as JSON, but it just does it in a different format. Thus, the two formats are commonly used for similar purposes -- sharing information on the web; however, because the format in which they do this is different, a different R package is needed to process XML data. This packages is called
xml2.
We will look into the
xml2 package a bit more when we look at importing html files.
# read XML file into R
read_xml("xml_file.xml")
