NEW YORK (AP) _ Stocks that have been moving substantially or trading heavily today on the New York Stock Exchange and Nasdaq Stock Market.

NYSE

AT&T rose 5 to 61 15/16.

The nation's No. 1 long-distance telephone company announced it will get a $5 billion investment from Microsoft Corp. in return for AT&T's increased use of the computer company's software.

Gap Inc. fell 5 1/4 at 64 1/8.

Although sales at many big retailers rose in April, the Gap clothing chain was hurt by an early Easter, which switched most holiday buying into March and skewed comparisons with a year ago.

NASDAQ

NorthPoint Communications Group Inc. , up 3 1/4 at 43 1/2

The San Fransisco-based high-speed Internet access provider's shares gained for a second day. The company sold 15 million common shares Wednesday in an initial public offering that drew investments from Microsoft and Tandy Corp.

Microsoft Corp., up 1 3/16 at 77 15/16

The software giant will invest $5 billion in AT&T Corp., which in return will increase its use of Microsoft's software.

At Home Corp down 1 3/16 at 153 3/4.

The Internet company was buoyed by the deal that AT&T, its part-owner, made with Microsoft and also by AT&T's planned purchase of MediaOne Group, the nation's fourth-largest cable company.