| Arraylist | Vector |
| Arraylist's methods are not synchronized which means they are not thread safe. | Vector's methods are synchronized which means they are thread safe. |
| It is not a legacy class. | It is a legacy class. |
| It is fast because it is non-synchronized. | It is slow because it is synchronized. |
| It uses an iterator interface to traverse the elements. | It uses an enumeration interface to traverse the elements, but it can also used iterator interface. |
It increases 50% in its capacity. | It increases 100% in its capacity. |
