Atom Tables are hash tables that are an efficient means of representing character strings as 16-bit integer values. There is one global atom table that is used for storing DDE atom values. Each application process can create one or more private atom tables that are visible only to their process.
The atom functions include:
| Function | Description |
| AddAtom | Creates an atom for a character string |
| DeleteAtom | Deletes an atom if the reference count is zero |
| FindAtom | Retrieves an atom associated with a character string |
| GetAtomHandle | Retrieves a handle (relative to the local heap) of the string that corresponds to a specified atom |
| GetAtomName | Copies the character string associated with an atom |
| GlobalAddAtom | Creates a global atom for a character string |
| GlobalDeleteAtom | Deletes a global atom if the reference count is zero |
| GlobalFindAtom | Retrieves a global atom associated with a character string |
| GlobalGetAtomName | Copies the character string associated with a global atom |
| InitAtomTable | Initializes an atom hash table |