When MIT first introduced MITx in December, we knew the courses would be popular. Not only are they free, but they allow anyone to receive an MIT-sanctioned certificate. With the first course launching today, however, we’re seeing just how popular the program is — 90,000 people popular. Coined “6.002x (Circuits and Electronics),” the class first opened in February, already garnering that immense amount of traffic.

“This is an exciting day,” said MIT Provost L. Rafael Reif, in a release. “MITx is designed to allow MIT students and faculty to explore ways to use technology to augment the MIT education: We are eager to see how MITx courses can add even greater value to our traditional, time-tested approach to teaching. MITx will also offer MIT teaching to people beyond our campus, widening access to education and offering new connections between the Institute and learners around the world.”

Modeled after MIT’s 6.002 — an introductory course for undergraduate students — 6.002x will introduce engineering in the context of the “lumped circuit abstraction,” helping students make the transition from physics to the fields of electrical engineering and computer science.

“The launch of our experimental prototype course is step one in a process we hope will lead to an innovative and effective online learning experience,” said Anant Agarwal, the director of MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) and the professor behind 6.002x. “We have built MITx in such a way that we will be able to release the software to the world as open source and to invite developers everywhere to help us improve the features we’ve created as well as invent new ones.”

To access the course, all students need to do is login here. There, they’ll find an introductory video describing how to use the platform, as well as a course schedule, an e-textbook for the course and a discussion board. Each week, students will be expected to watch video lectures and demonstrations, complete various homework assignments and participate in an online interactive lab specifically designed to replicate its 6.002, in-class counterpart. Overall, students will probably spend roughly 10 hours on the course once a week.

While the platform is interesting, what’s most fascinating is the amount of users who’ve already signed up. At 90,000 people, you’ve got a number that’s roughly 21 percent larger than MIT’s entire undergraduate class and 14 percent larger than its graduate class, according to numbers from College Board. Outside of MIT, over six million students are taking at least one online course and the Institute’s OpenCourseWare program has grown from 50 published courses to over 2,000.

It’s clear online education’s gone from a thought to a fully-fledged reality and is transforming how people think about the traditional brick-and-mortar institution. If 90,000 signed up for the first class alone, should we start wagering now how many will sign up for class two?