AUSTIN, Texas (AP) — Music flooded into the streets around Austin's convention center as South by Southwest's music festival kicked off and the interactive portion wrapped up. The head of Google's (X) division talked about testing driverless cars and delivery drones, gender bias in tech was a hot topic and event-goers checked out the latest products and companies on the trade show floor.

Here are some highlights as South by Southwest Interactive draws to a close.

GOOGLE X

Some of Google's most secretive projects like Google Glass and driverless cars have come out of its five-year-old (X) division, so attendees flooded in Tuesday to hear Astro Teller, head of the division, talk about how the most ambitious projects require a lot of failure before succeeding. Testing products in the real world is key, he said. The company drives thousands of miles on city streets every day to test how its driverless cars function in every imaginable situation. "Nothing beats going out into the real world and seeing if what a simulator says will work is actually possible," he said.

Working on creating unmanned delivery drones, Teller's team came up with a type of vehicle that sits upright and launches vertically, but there were some problems with it (Teller didn't say exactly what). Google co-founder Sergey Brin gave the team five months to be able to make deliveries by drone. They did it successfully in Queensland, Australia, but decided to go in a different direction with the drone project. Still, having the deadline helped the process advance, he said, and predicted there will be news about the drones later this year.

Teller also discussed Google's most high-profile failure, Google Glass, the wearable device which Google shuttered in January after it received a tepid response from users. The problem with Glass wasn't the device itself but the way they presented it to the public, he said. "We encouraged too much attention for the program," he said. "We wanted to say to the world this is an early prototype that we think is really exciting. But we also did things that encouraged people to think of this as a finished product."

GENDER BIAS IN TECH

The lack of gender diversity in tech received a jolt of attention after a talk on Monday between Aspen Institute CEO Walter Isaacson, U.S. Chief Technology Officer (and former Googler) Megan Smith and Google Executive Chairman Eric Schmidt. The subject of the talk was "How Innovation Happens" but topics ranged from immigration policy, getting top tech talent to work in the government, and connectivity deserts, or areas where it's hard for people to get online. Schmidt talked over Smith several times. During the Q&A conducted via Twitter, a listener pointed out how often Schmidt had interrupted Smith — and the audience applauded.

The panel had earlier discussed Ada Lovelace, Lord Byron's daughter, who wrote the first-ever computer algorithm but isn't well known as one of the founders of technology. (Her story is described in Isaacson's book "The Innovators"). Smith said it's crucial to make women aware of women's role in developing technology.

"Diversity makes better products," said Smith. "It's debilitating to not know technical women have been part of history from the beginning."

TECH IN THE SOUTH

The two 24-year old founders of Yik Yak, a messaging app wildly popular with college students, are proud to be based in Atlanta. Tyler Droll and Brooks Buffington told an audience on Monday that they have no plans to leave for more well-known tech hubs like Silicon Valley or New York.

"We're hometown heroes, we love Atlanta, that's where our families are from," Droll said. There's plenty of tech talent there too, added Buffington. "Not every single engineer comes from California, a lot of them are from the East Coast," Buffington said.

Billionaire investor Steve Case, co-founder of AOL, wants to support tech companies in smaller cities too. On Monday Case said he'll lead a bus tour across cities including Raleigh-Durham, North Carolina, Charleston, South Carolina and Atlanta dubbed "The Rise of the Rest" and hold pitch competitions for tech companies. He plans to invest $500,000 in the winners.

WINKLEVOSS TWINS TALK BITCOIN

The Winklevoss twins, Tyler and Cameron, are betting the digital currency bitcoin is here to stay. The brothers, known for suing Mark Zuckerberg over the idea for Facebook, on Monday promoted their new company Gemini, which they describe as a stock market for bitcoin. It's not operational yet, but in a panel Monday the twins said the digital currency could even replace gold as a stable currency.

"There's a certain inevitability to it, it's like the missing piece of the Internet," Cameron said. Tyler pointed out that bitcoin trading is already happening in China. "America is sitting on the sidelines," he said.

TRADE SHOW ANTICS

On the exhibition floor, small startups funded by Kickstarter showed off their products alongside bigger companies and organizations like NASA and IBM. At the NASA display, attendees could wear the virtual reality headset Oculus Rift to take a tour of Mars. A small company called Exiii displayed 3D-printed prosthetic limbs. At the booth for GMO Answers, a group funded by companies including Dow Agrosciences and Monsanto to try to improve the public's perception of genetically modified food, they were giving away potato chips made with a high-tech soybean oil called Plenish.

Giuseppe Taibi, a consultant from Lexington, Mass., was perusing the trade show floor on Tuesday. He was impressed by Jamit, a device that you insert into a violin to get real-time visual feedback to help improve your playing, since his daughter is learning the violin. And he was happy to talk to the makers of Tableau, a spreadsheet program he uses. "I got to have a Q&A with an expert," he said.

He enjoys the energy and networking at South by Southwest. "There are so many great ideas and everyone is in the mood for sharing," he said. "I'm sad to leave to go back to the snow in Boston."