whats the difference between ups converter or a inverter ?
There seems to be three terms used in this area, converter, inverter, and adaptor.
In general, a converter is a trasformer to "convert" the voltage from one value to another. The voltage may typically convert from 120 VAC to 220 VAC or vice versa.
An inverter is normally used to change direct current to alternating current. Like an inverter for your car would invert 12 VDC to 120VAC.
Last would be the term dc adaptor - this is usually used to change an alternating current to direct current with a trasformation, such as 120VAC to 9VDC.