Yahoo Inc. (YHOO) said Tuesday its quarterly profit doubled on Web advertising growth and issued a strong forecast for the current quarter, sending its shares up almost 6 percent.

The Internet media company's results and forecast topped Wall Street's estimates and also helped boost the shares of rival Google Inc. (GOOG).

"It looks like search revenue was particularly strong for Yahoo, which should bode well for Google," said Mark Mahaney, an analyst with American Technology Research, an independent firm that does no investment banking.

Web search advertising provides about half of Yahoo's revenue and virtually all of Google's.

Yahoo posted net income of $205 million, or 14 cents a share, in the first quarter, up from $101 million, or 7 cents a share, a year earlier.

Revenue excluding fees Yahoo pays its advertising partners grew to $821 million, up 49 percent from $550 million. Total revenue rose 55 percent to $1.2 billion.

Analysts on average had expected the company to post a net profit of 11 cents a share on net revenue of $798 million, according to Reuters Estimates.

Yahoo provides everything from e-mail, news, shopping, horoscopes and, increasingly, original content from its Web site Yahoo.com. It is the largest site in the United States in terms of monthly visitors, according to comScore Media Metrix (search).

The Sunnyvale, Calif.-based company forecast second- quarter revenue, excluding traffic acquisition costs of $855 million to $895 million, compared with analysts' average call for revenue of $841.8 million.

Yahoo shares rose 5.7 percent to $35.10 on the Inet electronic brokerage from a close of $33.22 on Nasdaq, while the shares of rival Google Inc. rose 4 percent to $199.