Email has had a good run as king of communications. But its reign is over.

In its place, a new generation of services is starting to take hold -- services like Twitter and Facebook and countless others vying for a piece of the new world. And just as email did more than a decade ago, this shift promises to profoundly rewrite the way we communicate -- in ways we can only begin to imagine.

We all still use email, of course. But email was better suited to the way we used to use the Internet -- logging off and on, checking our messages in bursts. Now, we are always connected, whether we are sitting at a desk or on a mobile phone. The always-on connection, in turn, has created a host of new ways to communicate that are much faster than email, and more fun.

Why wait for a response to an email when you get a quicker answer over instant messaging? Thanks to Facebook, some questions can be answered without asking them. You don't need to ask a friend whether she has left work, if she has updated her public 'status' on the site telling the world so. Email, stuck in the era of attachments, seems boring compared to services like Google Wave, currently in test phase, which allows users to share photos by dragging and dropping them from a desktop into a Wave, and to enter comments in near real time.

Little wonder that while email continues to grow, other types of communication services are growing far faster. In August 2009, 276.9 million people used email across the U.S., several European countries, Australia and Brazil, according to Nielsen Co., up 21% from 229.2 million in August 2008. But the number of users on social-networking and other community sites jumped 31% to 301.5 million people.

'The whole idea of this email service isn't really quite as significant anymore when you can have many, many different types of messages and files and when you have this all on the same type of networks,' says Alex Bochannek, curator at the Computer History Museum in Mountain View, Calif.

So, how will these new tools change the way we communicate? Let's start with the most obvious: They make our interactions that much faster.

Years ago, we were frustrated if it took a few days for a letter to arrive. A couple of years ago, we'd complain about a half-hour delay in getting an email. Today, we gripe about it taking an extra few seconds for a text message to go through. In a few months, we may be complaining that our cellphones aren't automatically able to send messages to friends within a certain distance, letting them know we're nearby. （A number of services already do this.）

These new services also make communicating more frequent and informal -- more like a blog comment or a throwaway aside, rather than a crafted email sent to one person. No need to spend time writing a long email to your half-dozen closest friends about how your vacation went. Now those friends, if they're interested, can watch it unfold in real time online. Instead of sending a few emails a week to a handful of friends, you can send dozens of messages a day to hundreds of people who know you, or just barely do.

Consider Twitter. The service allows users to send 140-character messages to people who have subscribed to see them, called followers. So instead of sending an email to friends announcing that you just got a new job, you can just tweet it for all the people who have chosen to 'follow' you to see. You can create links to particular users in messages by entering @ followed by their user name or send private 'direct messages' through the system by typing d and the user name.

Facebook is part of the trend, too. Users post status updates that show up in their friends' 'streams.' They can also post links to content and comment on it. No in-box required.

Dozens of other companies, from AOL and Yahoo Inc. to start-ups like Yammer Inc., are building products based on the same theme.

David Liu, an executive at AOL, calls it replacing the in-box with 'a river that continues to flow as you dip into it.'

But the speed and ease of communication cut both ways. While making communication more frequent, they can also make it less personal and intimate. Communicating is becoming so easy that the recipient knows how little time and thought was required of the sender. Yes, your half-dozen closest friends can read your vacation updates. But so can your 500 other 'friends.' And if you know all these people are reading your updates, you might say a lot less than you would otherwise.

Another obvious downside to the constant stream: It's a constant stream.

That can make it harder to determine the importance of various messages. When people can more easily fire off all sorts of messages -- from updates about their breakfast to questions about the evening's plans -- being able to figure out which messages are truly important, or even which warrant a response, can be difficult. Information overload can lead some people to tune out messages altogether.

Such noise makes us even more dependent on technology to help us communicate. Without software to help filter and organize based on factors we deem relevant, we'd drown in the deluge.

Perhaps the biggest change that these email successors bring is more of a public profile for users. In the email world, you are your name followed by a 'dot-com.' That's it. In the new messaging world, you have a higher profile, packed with data you want to share and possibly some you don't.

Such a public profile has its pluses and minuses. It can draw the people communicating closer, allowing them to exchange not only text but also all sorts of personal information, even facial cues. You know a lot about the person you are talking to, even before you've ever exchanged a single word.

电子邮件作为通信之王经历了飞速发展。不过它的统治时代已经终结。

新一代服务开始取而代之，比如Twitter、Facebook和其他无数争着想在新世界中分一杯羹的服务。如同10多年前电子邮件的出现一样，这一转变有望深刻地改写人们通信的方式──以我们刚刚能够开始想像得到的方式。

当然，我们仍会使用电子邮件。不过电子邮件更适合以往人们使用互联网的方式──隔三差五地登录、登出、查看信息。如今，我们总是联着网，无论我们是坐在桌子前还是用手机。这种总是联网的状态产生了一系列新的通信方式，比电子邮件要快的多，也有趣的多。

如果你可以通过及时消息更快地得到答案，为什么还要等待电子邮件回复呢？由于Facebook的出现，有些问题不必问就已经知道答案了。如果一位朋友更新了Facebook上的公开状态，告诉全世界她已经下班了，你就无需再问她了。与目前处于测试阶段的谷歌Wave等服务相比，拖着"附件"的电子邮件看起来要枯燥得多。通过谷歌Wave,用户可以把照片从桌面拖放到Wave中，与别人分享照片，并输入评论。

难怪在电子邮件继续增长之际，其他类型的通信服务却在以更高的速度增长。据尼尔森（Nielsen Co.）的数据，2009年8月，美国、欧洲的几个国家、澳大利亚和巴西有2.769亿电子邮件用户，较2008年8月的2.292亿增长了21%.而社交网站和其他社群网站的用户数量飙升了31%,至3.015亿。

加州电脑历史博物馆（Computer History Museum）馆长伯契纳克（Alex Bochannek）说，当你可以有很多很多不同种类的信息和文件，当你在同一种网络上拥有这一切时，电子邮件服务的概念就不再那么重要了。

那么，这些新的工具将如何改变我们通信的方式？让我们先看看最一目了然的方面：它们使我们的交流互动更快了。

很多年前，如果信件要几天才能到达，我们会感到沮丧不已。几年前，如果电子邮件接收迟了半小时，我们就会抱怨连连。而今天，如果一条文字信息的传送多花了几秒钟的时间，我们就会发牢骚。几个月后，我们可能会抱怨自己的手机不能自动地向一定距离内的朋友发短信，让他们知道我们就在附近。（已经有很多服务提供这样的功能了。）

这些新的服务还会使通信更频繁和随意──更像是博客评论或随便说出的话，而不是发给一个人的精雕细琢的电子邮件。无需花费时间给你那几个最好的朋友写长长的电子邮件，谈论你的假期过的如何。如今，如果这些朋友感兴趣的话，他们可以实时地在网上了解你的度假生活。你不是每周向屈指可数的几个朋友发送几封电子邮件，而是可以每天向数百个认识你或和你半生不熟的人发送几十条消息。

你可以考虑用Twitter.这个服务使用户可以向注册阅读用户（即关注者，followers）发送140个字符的信息。因此，你不用向朋友发封电子邮件，宣布你刚刚找到了一份新工作，你只要向所有选择"关注（follow）"的人"推（tweet）"一下就可以了。你可以在信息中创建特殊用户链接，只要输入@再加上他们的用户名，也可以通过输入"d"加用户名通过系统发送私人"直接消息".

Facebook也是这一趋势的一部分。用户可以更新状态，显示在朋友的"流"中。他们还可以发内容链接、对其进行评论。无需收件箱。

其他几十个企业都开始建立基于同样主题的产品，包括美国在线（AOL）、雅虎（Yahoo）和Yammer这样的初创企业。

美国在线的一位高管David Liu说，收件箱的替代品好像是"在你踏入其中，一条仍继续流淌的河".

不过，通信的速度和舒适性也是双刃剑。尽管可以使通信变得更频繁，却也可能使它变得更缺乏私密性。通信开始变得如此简单，收件人知道发件人只需很少的时间和思考。不错，你那几个最好的朋友可以阅读你的度假情况。不过你的其他500个"朋友"也可以。如果你知道所有这些人都在阅读你的更新，你可能就不会说那么多了。

持续不断流动的信息有着另外一个显而易见的不利因素：它是持续不断的。

这可能会加大判断各种信息重要性的难度。当人们可以更容易地发送从早餐到夜生活计划的各种各样的信息时，能够判断出哪些信息是确实重要的，或哪些需要回复，都不是轻而易举的事。过量的信息可能会导致一些人干脆对全部信息都置之不理。

这样的"噪声"使我们更加依赖于技术来帮助交流。如果没有软件帮助我们根据我们认为相关的因素对信息进行过滤和组织，我们就会淹没在海量的信息中。

或许电子邮件的这些接班人带来的最大变化是用户的公开信息增多。在电子邮件的世界里，你就是你的名字加上".com".仅此而已。在新的通信世界里，你的个人信息增多了，充满你希望与人分享的数据，可能还有一些你不希望与人分享的信息。

这样的公开信息有利也有弊。它可以让人们更近地交流，使他们不仅可以交流文字，还有各种各样的个人信息，甚至是面部表情。你会通过互联网非常了解和你对话的人，甚至是在你们真正开口说第一个字之前。