I'm not sure what to call this:
This is what's stored in a database field for a custom field type (date of birth) in an Interspire program written in php. I can kind of figure out what's going on a:2: seems to mean "two properties", i:0;s:3:"day"; means "first item, 3 character string, 'day' " ... and so on.
Question is: what do I call this? And is it a standardized format or specific to Interspire?
That looks like PHP serialized data. See http://www.php.net/manual/en/function.serialize.php#66147