Pretty much anything that's not a function is considered to be an object.
In general, the definition of object is incredibly wishy-washy and the word really ought to be retired, but as it stands, I don't think many people would agree that just any old piece of non-function data is an object. Different languages/people/formal systems have different definitions; for example, in Python, functions are themselves objects, while Java makes a clear distinction between objects and non-object primitive types like ints.
Mind you, this is as much a criticism of the original article's usage as yours; from a certain point of view (e.g. C++'s), C of course supports 'objects' inasmuch as you can store function pointers in structs and consequently have run-time selection of functions, after a fashion. From another point of view (e.g. Alan Kay's), even C++ does not have objects, because it lacks true message passing. The real criticism is that the term 'object' is so vague as to be essentially meaningless without clear context.
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Minor semantic point:
In general, the definition of object is incredibly wishy-washy and the word really ought to be retired, but as it stands, I don't think many people would agree that just any old piece of non-function data is an object. Different languages/people/formal systems have different definitions; for example, in Python, functions are themselves objects, while Java makes a clear distinction between objects and non-object primitive types like ints.Mind you, this is as much a criticism of the original article's usage as yours; from a certain point of view (e.g. C++'s), C of course supports 'objects' inasmuch as you can store function pointers in structs and consequently have run-time selection of functions, after a fashion. From another point of view (e.g. Alan Kay's), even C++ does not have objects, because it lacks true message passing. The real criticism is that the term 'object' is so vague as to be essentially meaningless without clear context.