Object vs. Map

How Do You Compare Object and Map?

Feature	Object	Map
Key types	Only strings and symbols are valid keys.	Any value can be used as a key (objects, functions, primitives).
Key order	Keys are unordered (in practice, insertion order is mostly preserved for string keys, but not guaranteed).	Keys are ordered by insertion; iteration follows insertion order.
Size property	No built-in way to get the number of keys; use Object.keys(obj).length.	Use the .size property for the number of entries.
Iterability	Not directly iterable; use Object.keys, Object.values, or Object.entries.	Directly iterable with for...of, .keys(), .values(), and .entries().
Prototype	Has a prototype chain; default properties can collide with custom keys (can be avoided with Object.create(null)).	Does not have a prototype, so there are no default keys.
Performance	May be less efficient for frequent additions and removals.	Optimized for frequent additions and deletions.
Serialization	Can be easily serialized to JSON.	Cannot be directly serialized to JSON.