The primary difference between the DOW, S&P 500 and the NASDAQ is not truly what composes each index, it is about capital flows. All the way up, it was the DOW which made new highs first with the other two following the Dow's lead. Now, the cash flows are showing a broader diversification with the S&P 500 a touch stronger. Here the Daily Bullish stands at 212850. It has been the NASDAQ making new highs and taking the lead. The Daily Bullish Reversal here stands at 516440 and the intraday high is clearly in June compared to May for the Dow and the S&P 500. The Daily Bullish in the Dow stands at 18233 and 18371.
A closing today above 1788900 in the Dow today will keep it positive for now. However, we need a closing above 18243 to imply a continued immediate rally. In the S&P 500, we did achieve a minor Weekly Bullish last week but here we need a closing on our weekly mode above 211510 to signal an immediate continued rally. In the NASDAQ, a weekly closing above 514335 is required for a breakout to the upside.
The DOW tends to reflect international big money. The S&P 500 tends to reflect general broad institutional investment whereas the NASDAQ tends to imply more retail. This is simply a general rule that distinguishes the players and capital flows. There are exceptions at times, but this is just a general guideline rather than a black and white rule.