Чем отличаются Wh от Ah

I'll try to explain the difference between watt-hours and ampere-hours as best I can, since battery capacity is most often indicated in ampere-hours (Ah). However, this system only applies to a single battery voltage; at different voltages, it's practically impossible to compare battery capacities in Ah; you need to convert them to watt-hours. Honestly, this simple shortcut was difficult; I rewrote it three times and couldn't make sense of it. Educational content is clearly not my thing.