An equity index is a weighted basket. The S&P 500 covers large US companies across sectors. The NASDAQ-100 is heavier in technology. Trading them as CFDs lets you take a view on the basket rather than on a single share.
Because the basket is diversified, a single earnings print is usually less violent than it would be on one name. The trade-off is that sector leadership still matters: a technology-led rally can lift the NASDAQ more than the S&P 500.
Session rhythm
US cash hours remain the most active window. Overnight futures can gap into the open, so the first minutes after the cash open often carry more range than a quiet afternoon.
Use the index as a backdrop for other books as well. A sharp drop in US indices can spill into USDJPY or into gold. Reading the index first is a fast way to judge whether the day is risk-on or defensive.
