"Income" and "wage" are used interchangeably in this context - income derived from labour, ie salary, bonuses etc. That's what "income inequality" generally refers to.
"Wealth inequality" is what's relevant if you're concerned about the mega-rich like Jobs. If your assets are big enough you can live off of them without any labour - through rents, dividends, sale of assets etc.
It's interesting if income inequality is going down considering that wealth inequality is worsening in the developed world due to the recent massive inflation of housing assets.
Easily explained, the assets became unavailable to whole chunk of population, and the relatively tiny increase of wages does barely dent the increased cost of living for them.
The remaining assets are purchased by the rich who can afford them.
Easiest way to present this problem would be to measure in PPP adjusted dollars the time it takes to save to purchase a basic asset (usually living space) subtracting living costs. Make sure to also consider the asset price long term trend while at it.
If you cannot save, the time is infinity, if you cannot buy it in a lifetime, better also count your (ever poorer) kids in.
This is only the most basic estimate, remember that over time any health issue or other catastrophe is likely to happen, and the response to these often depends the savings you have... (You can count a flat buffer or a percentage.)
"Wealth inequality" is what's relevant if you're concerned about the mega-rich like Jobs. If your assets are big enough you can live off of them without any labour - through rents, dividends, sale of assets etc.
It's interesting if income inequality is going down considering that wealth inequality is worsening in the developed world due to the recent massive inflation of housing assets.