Practically speaking, what is the difference between arrays and pointers?

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Practically speaking, what is the difference between arrays and pointers?

An array is a single, preallocated chunk of contiguous elements (all of the same type), fixed in size and location. A pointer is a reference to any data element (of a particular type) anywhere. A pointer must be assigned to point to space allocated elsewhere, but it can be reassigned (and the space, if derived from malloc, can be resized) at any time. A pointer can point to an array, and can simulate (along with malloc) a dynamically allocated array, but a pointer is a much more general data structure.
Due to the so-called equivalence of arrays and pointers, arrays and pointers often seem interchangeable, and in particular a pointer to a block of memory assigned by malloc is frequently treated (and can be referenced using []) exactly as if it were a true array.

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