What’s Equal?

I always wonder what is fairness and equality; is equal opportunity or equal outcomes fair? Why do we have that instinctive fairness protest while being able to tolerate some degree of what would be considered ‘unfairness’? Is meritocracy fair?

So for the guy who is disabled, is it fairer that we make sure he gets to the second level perhaps by installing a lift or do we force him to crawl/walk up the stairs just as everyone else do? True meritocracy leaves no room for charity and we must thus acknowledge the limits of applying that argument on incentives and solutions to various different problems.