UPS and Inverter work same way. But inverter is build to provide backup electricity for TV, FAN, Fridge, Light etc… UPS is for computers.
UPS produces exact sine wave via microprocessors, but inverter produces what is called a Square Wave (TPZi) waveform which uses less battery power for longer backups. There are few modern inverters that produce better wave form, but you can’t say this to all inverters.
Inverter is not considered safe for using with Computer.
UPS have faster switching speed compared to an Inverter.
Inverters are made for home appliances that use less power and not as sensitive as computers.
Computers are very highly sensitive equipments. On the contrary a TV also uses a embedded chips for processing data. TV is also sensitive, but not as sensitive as the computer.
Most ups have a noise/surge filter built in that protect the computer from sudden change in power.
Another plus for UPS’s are they are made according to strict IEC standards and switch over time must be within certain parameters provided the topology is Line Interactive.
Furthermore UPS’s can usually also correct frequency and voltage dips/peaks (within constraints) but will switch automatically to battery mode if the power is unacceptable.
For long run times a generator backup + UPS is the most cost effective solution. Very long run time from UPS alone can be expensive due to battery cost.
There can be few inverters that work good with computers, but we can’t say this for all Inverters. If you are buying for Computer, better buy a USP that is primarily made to provide backup for computer.