an edge means you produce something you expect.
for example, you see a market, then you guess/predict it will go up and to what extent in what time period. and it really does as you expected, that is an edge.
another example, you read newsheadlines, and you easily figure out what bulls are thinking and so do bears. the ability to get the market theme from a little bit clues. that is an edge.
or some people act very quickly with no thinking, that is an edge too. in a fast moving market, they can produce huge profits based on the order flow and quick reflective ability under uncertainties. most people will get rational, or be frozen, but often too late end up chasing.
or some people build a system, produce statistic positive results, that is an edge too.
anything can be an edge. different people have different intelligence, personalities, qualities,... so each people should have its own edge. some people's edge may be yours shortcoming.
to an institution, they may need a machinical system, apply money management, risk control model, .... or act as Market makers to scalping do HLF aglorithm trading, very suitable to them.
but to an individual retail trader, that is not en edge. first, you are not deep pocket, you can not win statistically. but you have your own strength. you can act swiftly, your position will not affect the market at all (that provides convinece for you to get in and get out freely). you can just zoom in particular target, you can hit right with higher rate, even with 9 out of 10. you can switch from this strategy to that strategy, or from this symbol to another. this is the benefits of being small.
the big disadvantage of being small is:
you need take advantage of those big players. if you want to fly, you need an airplane (big players). since your existence to the market means nothing, you can notmove the market at all. the only youcan benefit is follow those big players.
if ant need walk 10miles, sneek on an horse, that will be fast.