Solved: What does in XML mean?


I often find this strange CDATA tag in XML files:
I have observed that this CDATA tag always comes at the beginning, and then followed by some stuff.
But sometimes it is used, sometimes it is not. I assume it is to mark that some stuff is the “data” that will be inserted after that. But what kind of data is some stuff? Isn’t anything I write in XML tags some sort of data?

Best Answer:

CDATA stands for Character Data and it means that the data in between these strings includes data that could be interpreted as XML markup, but should not be.
The key differences between CDATA and comments are:

This means given these four snippets of XML from one well-formed document:

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