It’s impossible to explain Twitter to the common internet user without sounding really retarded. “What does it do?” “How could that be popular?” At first I couldn’t understand how a whole application could be built around just “posting away messages.” Unlike email, message boards, or blogs, it’s not clear whether Twitter has any offline behavioral metaphor. If it doesn’t clearly mimic anything in real life, how do people know how to use it? How would people understand it’s value? And we still haven’t answered: what the hell is Twitter, and what makes it popular?

Because message boards and blogs were too structured and rigid

Twitter shares many features with away messages, wall posts, and micro-blogging. What do these have in common? They are convenient, public, and most importantly, casual.

1. Casual—
   Twitter addresses a conversation space that message boards and blogs failed to address: rapid unstructured chatter. Forums are rigidly locked into sections and formally defined threads. The problem is that in real-life casual conversation, threads are incredibly ephemeral, they weave in and out too quickly for anyone to bother defining. With the exception of time and proximity, we don’t normally use any formal structures to manage threads! But yet, if you look at blogging and forums, the traditional methods of public discourse, they are cluttered with manually defined meta-data. Content is categorized, tagged, threaded, dated, titled, sub-titled, stickied, closed. This kind of stuff slows down the pace of conversation. Twitter doesn’t have any of that shit.

   Twitter models conversation behavior by stripping out most of the structure in content, leaving behind only two attributes for each tweet: time and person addressed, which is exactly how much metadata you’d find in real life conversations.

2. Public—
   The other cool thing is how easy it is to overhear other streams (of eavesdrop if you will). Imagine 8 friends standing together at a bar. At first people converse in pairs—they are engaged, but could easily overhear the other conversations. This leads to the rapid merging and unmerging of threads you see on Twitter. It’s just so easy to pick up interesting bits and jump into conversations, bringing back the level of engagement you could only find in physical proximity.
3. Convenient—
   And of course, the most visible strength of Twitter is the sheer number of ways one could send and receive updates. No need to delve into this…

The magic comes together

So the magic comes from letting groups of people across the world mimic close-proximity conversation. If forums are discussion and blogs are publishing, what is Twitter? Some suggest, presence, others, grabage; but I think it’s simply natural public conversation (minus the intimacy of IM).

One thing to note: Twitter works great for groups of friends who are geographically spread out—the dominant usage pattern today. But is it useful for friends closeby? The answer isn’t obvious; after all, instant-messaging supposedly mimics direct conversation but it bloomed with high schoolers who see each other every single day…