For many in the tech world, the calendar in early March is dominated by one thing: South by Southwest Interactive.

The 21st annual tech festival officially starts on Friday, bringing an expected crowd of 30,000 people, including some of Big Tech's biggest names, eager entrepreneurs, savvy investors, and tech groupies, to Austin, Texas. Over the last decade, the festival has become the launchpad for startups (including Twitter) and is generally considered a celebratory morass of tech geekdom.

This year, the five-day event has over 800 sessions, and common themes throughout include 3D printing, wearable tech, and privacy issues.

But if you're looking for a quick hit list of the big highlights, here's what you need to know:

Sophia Amorouso's secret to fast growthIn a conversation with Inc.'s own Christine Lagorio-Chafkin, the NastyGal founder will reveal Saturday how she turned her eBay store into a full-fledged, $100 million retail powerhouse. But it's not just a talk about scaling: the cheeky entrepreneur is known for her badass attitude which has also built her a brand to be reckoned with. 

Alexis Ohanian's rebel call. In an event dubbed "Be Awesome Without Their Permission," reddit cofounder and Internet activist Alexis Ohanian will talk Sunday about the distinct advantages startups have when it comes to bucking the rules--and making big impact.

Whistleblowers Edward Snowden's and Julian Assange's satellite speeches. In an 11th hour surprise, SXSW announced this week that fugitive Edward Snowden will be speaking via satellite feed on Monday. Snowden will be interviewed by the ACLU's Ben Wizner. According to CNN, Snowden "wants to talk to a tech-focused audience about the importance of building the next generation of online tools that protect user privacy." And on Saturday, Wikileaks founder Julian Assange will have a "virtual conversation" with the Barbarian Group's Benjamin Palmer, in which they will discuss the "Internet Nation" and the role of classified documents in the public arena.

Ben Horowitz's take on the dark side. The cofounder of Andreessen Horowitz sits down on Sunday with the hip-hop star Nas to discuss the emotional struggles startups face as they enter into a rapid-growth phase, and how he himself has personally faced some of these struggles. 

Chelsea Clinton's health keynote. The Clinton Foundation Vice Chair (and daughter of arguably two of the most influencial politicians of our time) will take the stage Tuesday to talk specifically about global health issues and the programs aiming to stop them.

Okay, all the keynotes. Of course, you'll not want to miss any of the keynote talks this year. The list includes Mythbuster's host and science geek Adam Savage and astrophysicist Dr. Neil deGrasse Tyson, to name a few. Here's the full line up. 

Biz Stone's one-on-one. The cofounder of Twitter and current cofounder of the high-profile image discovery platform Jelly will speak on Tuesday. Though there's not much detail about what the conversation, which is hosted by author Steven Johnson, will cover, so far we know it will at least cover the broad areas of "connected society, the science and nature of collaborative networks, creativity, and how great ideas are born into existence."

If you'd like to comb through all 800 sessions yourself to find more, you can check out the SXSW website