Most indexes, like the S&P 500 and Nasdaq Composite, assign a higher weighting to the largest companies by market cap. For example, Apple has roughly 11 times the market cap of Coca-Cola, so it has a much higher weighting in the S&P 500. But in the Dow, Apple is the 12th highest-weighted company by market cap because the index is price-weighted.

Intel will be replaced by Nvidia on the blue-chip Dow Jones Industrial Average index after a 25-year run, underscoring the shift in the chipmaking market and marking another setback for the struggling semiconductor firm.

Nvidia joins the DJIA amid cyclical highs, but past trends suggest caution. Find out why NVDA stock may struggle despite the prestigious inclusion.