It sounds like a science-fiction nightmare. But "killer robots" have the likes of British scientist Stephen Hawking and Apple co-founder Steve Wozniak fretting, and warning they could fuel ethnic cleansing and an arms race.

Autonomous weapons, which use artificial intelligence to select targets without human intervention, have been described as "the third revolution in warfare, after gunpowder and nuclear arms," around 1,000 technology chiefs wrote in an open letter.

Online retail colossus Amazon wants to carve out a special zone of the sky to shuttle commercial drones that would deliver goods to its customers.

Amazon Prime Air project vice president Gur Kimchi used a NASA convention in California on Tuesday to fly the idea of dedicating separate air zones for commercial drones.

Sri Lanka teamed up on Tuesday with Google to bring high-speed Internet access to the island using balloons, aiming to become the first country in the region with complete coverage. 

Foreign minister Mangala Samaraweera said officials signed an agreement with Google in the capital Colombo to launch the helium-filled, high-tech balloons above the Indian Ocean island in coming months.

Microsoft's new Windows 10 operating system debuts Wednesday, as the longtime leader in PC software struggles to carve out a new role in a world where people increasingly rely on smartphones, tablets and information stored online.

No one's expected to line up overnight for Windows 10, the way people did 20 years ago for Windows 95. But Microsoft is counting on tens or even hundreds of millions of people to download its latest release for free in the coming months. The launch will be accompanied by a global marketing campaign for an event the company hopes will be pivotal — both for its own future and for a vast audience of computer users around the world.

Google on Monday said it is throttling back on its vision of having profiles at its social network serve as people's identities across its range of online offerings.

"Important changes" coming to Google+ in the months ahead will include users no longer needing an account at the social network to post videos or comments at YouTube.

The National Security Agency will cease its access to most bulk data collected under a controversial surveillance program in November, but retain records for litigation purposes, officials said Monday.

The office of the Director of National Intelligence said in a statement that the bulk telephony data -- the subject of leaks by former intelligence contractor Edward Snowden which shocked many in the U.S. and abroad -- would be destroyed "as soon as possible" to comply with a law passed by Congress in early June.

Cyber security firm Zimperium on Monday warned of a flaw in the world's most popular smartphone operating system that lets hackers take control with a text message.

"Attackers only need your mobile number, using which they can remotely execute code via a specially crafted media file delivered via MMS (text message)," Zimperium Mobile Security said in a blog post.

China is lifting its ban on sales of video game consoles to promote the industry and a new manufacturing zone in Shanghai.

Consoles produced in the Shanghai Free-Trade Zone will automatically be approved for sale in the rest of China, according to a Ministry of Culture notice dated Friday.

As President Barack Obama faces pressure to discuss human rights in his first official visit to Ethiopia this weekend, a unique lawsuit back home is challenging whether the African country can spy on an American by turning his computer into a giant recording device.

The federal case alleges Ethiopian government agents gobbled up months of a Maryland man's Skype calls and his family's Internet activities. But the man, born in Ethiopia and now a U.S. citizen, isn't wanted for a crime. Instead, he helps out a political opposition group outlawed in his home country.

Microsoft is aiming to build lasting relationships with Windows 10, the operating system to be launched on Wednesday and seen as critical to reviving the fortunes of the once-dominant tech giant.

For the first time, Microsoft is making a major new version of Windows available free as an upgrade to anyone using either of the prior two generations of the system.