Former Microsoft CEO Steve Ballmer announced today he is stepping down from Microsoft's board.

The game of musical chairs continues at Twitter, where co-founder and former CEO Evan Williams will step down as product development leader, a role that will be taken over by Jack Dorsey, another co-founder who had distanced himself from the company's daily operations.

Longtime Microsoft executive Bob Muglia, president of the company's server and tools business, will step down from his position later this year, according to a Steve Ballmer memo issued Monday to company employees.

Ray Ozzie, Microsoft's chief software architect and the executive responsible for pushing the company into the cloud, plans to step down, Microsoft said on Monday.

The former CEO is widely credited for turning around the company.

RealNetworks' founder, Rob Glaser, is stepping down from his role as CEO, the company announced on Wednesday.

Chris DeWolfe will hand over his CEO title at MySpace, whose growth has stagnated over the past year while the popularity of rival Facebook booms.

Symantec CEO John Thompson is retiring. Thompson, 59, has led the Cupertino, California, security vendor for the past decade.

After a bungled buyout offer from Microsoft, a deal with Google that fell apart and two rounds of layoffs, Jerry Yang is calling it quits and stepping aside as chief executive of the company he cofounded, Yahoo said Monday.

Alcatel-Lucent's CEO Patricia Russo plans to step down before the end of the year, and Chairman Serge Tchuruk will quit on Oct. 1. Russo will stay on until the board finds a replacement, the company said Tuesday.

Vodafone Group CEO Arun Sarin will step down from the top job at the mobile operator in July, the company said Tuesday.

EBay exceeded Wall Street's earnings and revenue expectations for its fourth quarter and, as expected, announced that Meg Whitman will step down as president and CEO at the end of March, ending a 10-year tenure at the helm of the e-commerce giant.