Objects

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Arrays are great for ordered collections you look up by numeric position — but a lot of real data is more naturally described by name than by position. An object holds key-value pairs inside curly braces { }: each value is looked up by a meaningful name (its key) rather than an index.

You can read a value two ways: dot notation (player.name) is the shorter, more common form when you already know the key name; bracket notation (player["name"]) works the same way but is required when the key is stored in a variable or contains characters that aren't valid in dot notation (like a space).

Think of an object as describing "one thing with several properties" — a player has a name and a score, a car has a make and a model — whereas an array is better suited to "many things of the same kind in a row." Real programs frequently combine both: an array of player objects, for instance.