Every day for the last couple weeks has been a record traffic day for us at Quizlet. It’s awesome to see so many people using Quizlet — we now have over 500,000 registered users and 3,000+ new ones per day. Quizlet users have uploaded more than 33,000,000 flashcards. Our traffic has grown 80% just over last week. Nice work, guys!

Some of you may have noticed some spotty service on Quizlet in the last few days. We’ve simply become overloaded with our popularity. Unfortunately for us, that means we have to bring the site down briefly to add more server capacity. We’re going to do this sooner rather than later — i.e. TODAY!

We’re expecting to go down around 5pm EST for as many as 5 hours (if all goes well, it’ll be less). We’ll be keeping everyone updated on our quizlet twitter feed. We know it’s short notice and extremely inconvenient, so thank you very much for your patience.

Today we’re announcing some major new functionality on Quizlet: image-based studying. It’s been one of our all-time most requested features, so we’re super excited to make it available to every one. On Quizlet so far, everything has been plain text: you type in a word, and you type in a definition. Now you can study visually.

One of the major upgrades is to the “create set” page that let’s you enter flash cards. Here’s what it looked like before:

Here’s what it looks like now:

The import data and flip terms links are easier to find, the auto-definer is easier to use (that’s what the mysterious question mark used to do). If you didn’t know, the auto-definer looks up definitions in a dictionary (Source: WordNet), and also pulls up definitions that other users entered (but only in public sets). And overall, the input boxes are wider so you can fit more data in visually without scrolling.

But that’s just cosmetic — the really cool thing is the new “add image” feature.

All you have to do is click “add image” and we automatically find you an image from Flickr, an awesome image hosting service with a great developer platform and lots of Creative Commons-licensed images that let us use the images for free, as long we credit the authors (which we do).

Of course, if you don’t like the first image that pops up, you can get the next one.

Or the next one…and so on. You can also refine your search, so if you don’t like any of the images, you can type a special search in the “Find Images” box that is independent of your term and definition.

Also, you can use just images and have no definition, or you can use Quizlet like before without images, or you can use both at the same time. It all works seamlessly.

Now, how about studying? Images are fully integrated into all the existing study modes. Check it out:

Familiarize:

Learn:

Test:

Scatter

Space Race

It’s wicked cool. If you want to play with a real live image set, check out this list of french animals with images. I hope to add more FAQs and a showcase of image sets so you can see more examples — the possibilities are limitless.

One really cool use-case is for foreign language and english-as-a-second-language (ESL) learning, where you may have 30 students in a class who come from 8 different countries. If you were to say a fish is something that swims in the water, that wouldn’t be useful, partly because the students wouldn’t necessarily all understand the english definition to an english word. But with pictures, well, they speak for themselves.

Now, you may be wondering, can you upload your own images instead of using Flickr?

Not yet, but you will be able to soon. We plan to allow uploading images very soon as a paid upgrade. As always, Quizlet will remain free to all users and we won’t be removing any functionality for non-paying members, but we may be adding some additional powerful features to paying members. We will have more information on this soon.  Uploaded images would be especially useful to medical school students who need to study special diagrams or art history students who need to study obscure paintings or sculptures.

Also, our thanks to the people who have become friends of Quizlet by donating to Quizlet. Their support has helped make this feature and other future upgrades possible.

Developers: Look for an update to the Quizlet API in the next week or so with image abilities.

It’s been awhile since I’ve updated the blog, so it might be hard to believe that a lot of work has gone into Quizlet since the last post. We’ve made the Quizlet search engine a ton better, we’ve added some exciting new technology that does voice recognition (more on that later), and made a lot of performance enhancements to keep the site running as growth increases.

Now, as we head into summer (and the accompanying dive in traffic as people get of school), we have the opportunity to experiment with lots of cool new features. We’re building a lot of cool tools set to be done before the summer is up — one of which we’re ready to announce today:

The Quizlet API is now available! For those who don’t know, API stands for Application Programming Interface. The Quizlet API is a tool that lets programmers develop tools that work with Quizlet’s massive content library (we now have about 30 million flashcards on our site!) This will let people build cool things like cell phone applications and screensavers that use Quizlet data. Developers have been asking for this for years, so it’s great that it’s finally available.

The Quizlet API is free to use and only requires you to be a registered Quizlet user (which you can also get for free). This is our first release so you may not be able to do everything you want just yet, but you should find that it’s surprisingly powerful. If you have suggestions for stuff we should add or bugs you find, please post a comment in the blog.

Are you a developer? Get started here.

Hey! We have lots of improvements to announce today! In random order:

We’ve started a donations page to let Quizlet users who appreciate our free service to donate towards future improvements to Quizlet. If you find Quizlet useful, please consider donating $10 or more. Donating will also remove all advertising from your account for 1 year. You also get this cool button on your user page:

Improvements to Space Race:

• Words move a little bit slower
• The game now ends when you run out of lives instead of when you miss two words in a row.
• The last answer before the game ends is now displayed.

Your Facebook friends list is now refreshed at regular intervals.

Users who are 13 but were born in the first few months of 1996 were allowed to sign up but not use the site. This is fixed, and we apologize for this annoying problem.

The accents bar now remembers when you turn it off on the Make Flashcards page.

Applications to groups now send group administrators the message the user included in their application.

We’ve updated our Terms of Service to clarify what is and is not acceptable content on Quizlet. We strongly recommend all Quizlet users take a look at this document.

We’re improving our Frequency Asked Questions section and opening the FAQs up to user suggestions, so that users can now add their own information to an FAQ.

We have a lot of projects we’re making progress on. Here are some of the things we’re focusing on:

• The Quizlet iPhone app is making slow and steady progress. It will work offline, and sync with your Quizlet account to download all of your sets. It’s going to be worth the wait.
• Improvements to speed and usefulness of the Search/Content Finding functionality on the site.
• Continuing to improve the Facebook environment on Quizlet, and making it easier to invite and find your friends on Quizlet.
• A top-secret project in collaboration with MIT. You’ll hear more in the next month.

And of course, we’re always working on keeping the site speedy and reliable as Quizlet grows. I almost forgot to mention that there are now more than 400,000 registered Quizlet users, who create more than 100,000 flashcards every day. That’s a lot of studying!

And don’t forget to follow us on twitter!

Do these things sound good? Your donation will make them happen faster!

Last thing: We’re looking for a summer intern to work on these projects in San Francisco. More information is coming soon. Interested? Email jobs@domainisobvious.com

Today we’re launching Facebook on Quizlet. This feature lets you use your Facebook account instead of a Quizlet account to log in to Quizlet. This removes the need to create a Quizlet account with a password and email address and birth day–you just use your Facebook!

If you already have a Quizlet account, you can use both. If you do authorize Facebook with an existing Quizlet account, Facebook features on the site will only show when you are also logged into Facebook (there will be helpful prompts that show you how to do this).

In addition to logging in with Facebook, you can do some special Facebook things within the site:

When you post a new set (that’s not private), you have the option to post a link to it on your Facebook page, so that your friends on Facebook can see what you’re studying:

You can also see your currently online Facebook friends that are also studying on Quizlet. The My Groups page becomes My Friends and you’ll see something like this:

If you’ve added Facebook to your Quizlet account and want to remove it, you can do that in your preferences page (link at the top-right corner).

This is just the first start on the Facebook project — giving you the basic features developers Facebook gives you to integrate websites. As we hear suggestions and explore the platform more, we’ll add things that make this integration even more useful.

So, what do you guys think? Let us know

P.S. I also slowed down Space Race a little and made some bug fixes. Post a comment if you see something amiss. Thanks!

Hey all–

We’ve made a ton of progress so far on our big January push. We’re finishing up the last touches on Facebook Connect, the iPhone app is coming along well, and one of our super secret projects is on track to make a big splash.

In order to communicate quickly, I’ve decided to get a Quizlet twitter account. Is Quizlet down? Having issues? There’s a good chance you’ll find some quick info on Twitter. I’ve been skeptical of Twitter for awhile, but with all the chatter about it these days (see this awesome super bowl visualization, I figured I’d give it a try.

That’s all for now, just wanted to keep everyone in the loop. Expect some big things in the next couple weeks