XML Processing instructions allow documents to contain instructions for applications. PI consists of two parts: 1.

target

- Identifies the application to which the instruction is directed. 2.

instruction

- A character that describes the information for the

target

application to process. ... PI's example in real XML document

<?xml version="1.0" encoding="UTF-8"?>
<student>
    <?sort alpha-ascending?>
    <?textinfo whitespace is allowed ?>
    <first-name>George</first-name>
    <phone.mobile>(011) 123-4567</phone.mobile>
</student>

In this example we have two PIs 1.

sort

with value -

alpha-ascending

2.

textinfo

with value -

whitespace is allowed

... Note: processing instructions can contain any data except the combination

?>

, which is interpreted as a closing delimiter