Due to investors' optimism about the prospects of artificial intelligence (AI), coupled with reduced uncertainty in trade policies, US stocks closed higher today, with the Nasdaq index, which is dominated by tech stocks, continuing to set new highs. The Dow Jones Industrial Average rose 206.97 points or 0.47%, closing at 44,175.61 points. The S&P 500 index rose 49.45 points or 0.78%, closing at 6,389.45 points. The Nasdaq index rose 207.32 points or 0.98%, closing at 21,450.02 points. The Philadelphia Semiconductor Index rose 44.315 points or 0.79%, closing at 5,678.016 points.