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+Erlang and the Web
+==================
+
+The Web is concurrent
+---------------------
+
+When you access a website there is little concurrency
+involved. A few connections are opened and requests
+are sent through these connections. Then the web page
+is displayed on your screen. Your browser will only
+open up to 4 or 8 connections to the server, depending
+on your settings. This isn't much.
+
+But think about it. You are not the only one accessing
+the server at the same time. There can be hundreds, if
+not thousands, if not millions of connections to the
+same server at the same time.
+
+Even today a lot of systems used in production haven't
+solved the C10K problem (ten thousand concurrent connections).
+And the ones who did are trying hard to get to the next
+step, C100K, and are pretty far from it.
+
+Erlang meanwhile has no problem handling millions of
+connections. At the time of writing there are application
+servers written in Erlang that can handle more than two
+million connections on a single server in a real production
+application, with spare memory and CPU!
+
+The Web is concurrent, and Erlang is a language designed
+for concurrency, so it is a perfect match.
+
+Of course, various platforms need to scale beyond a few
+million connections. This is where Erlang's built-in
+distribution mechanisms come in. If one server isn't
+enough, add more! Erlang allows you to use the same code
+for talking to local processes or to processes in other
+parts of your cluster, which means you can scale very
+quickly if the need arises.
+
+The Web has large userbases, and the Erlang platform was
+designed to work in a distributed setting, so it is a
+perfect match.
+
+Or is it? Surely you can find solutions to handle that many
+concurrent connections with my favorite language... But all
+these solutions will break down in the next few years. Why?
+Firstly because servers don't get any more powerful, they
+instead get a lot more cores and memory. This is only useful
+if your application can use them properly, and Erlang is
+light-years away from anything else in that area. Secondly,
+today your computer and your phone are online, tomorrow your
+watch, goggles, bike, car, fridge and tons of other devices
+will also connect to various applications on the Internet.
+
+Only Erlang is prepared to deal with what's coming.
+
+The Web is soft real time
+-------------------------
+
+What does soft real time mean, you ask? It means we want the
+operations done as quickly as possible, and in the case of
+web applications, it means we want the data propagated fast.
+
+In comparison, hard real time has a similar meaning, but also
+has a hard time constraint, for example an operation needs to
+be done in under N milliseconds otherwise the system fails
+entirely.
+
+Users aren't that needy yet, they just want to get access
+to their content in a reasonable delay, and they want the
+actions they make to register at most a few seconds after
+they submitted them, otherwise they'll start worrying about
+whether it successfully went through.
+
+The Web is soft real time because taking longer to perform an
+operation would be seen as bad quality of service.
+
+Erlang is a soft real time system. It will always run
+processes fairly, a little at a time, switching to another
+process after a while and preventing a single process to
+steal resources from all others. This means that Erlang
+can guarantee stable low latency of operations.
+
+Erlang provides the guarantees that the soft real time Web
+requires.
+
+The Web is asynchronous
+-----------------------
+
+Long ago, the Web was synchronous because HTTP was synchronous.
+You fired a request, and then waited for a response. Not anymore.
+It all started when XmlHttpRequest started being used. It allowed
+the client to perform asynchronous calls to the server.
+
+Then Websocket appeared and allowed both the server and the client
+to send data to the other endpoint completely asynchronously. The
+data is contained within frames and no response is necessary.
+
+Erlang processes work the same. They send each other data contained
+within messages and then continue running without needing a response.
+They tend to spend most of their time inactive, waiting for a new
+message, and the Erlang VM happily activate them when one is received.
+
+It is therefore quite easy to imagine Erlang being good at receiving
+Websocket frames, which may come in at unpredictable times, pass the
+data to the responsible processes which are always ready waiting for
+new messages, and perform the operations required by only activating
+the required parts of the system.
+
+The more recent Web technologies, like Websocket of course, but also
+SPDY and HTTP/2.0, are all fully asynchronous protocols. The concept
+of requests and responses is retained of course, but anything could
+be sent in between, by both the client or the browser, and the
+responses could also be received in a completely different order.
+
+Erlang is by nature asynchronous and really good at it thanks to the
+great engineering that has been done in the VM over the years. It's
+only natural that it's so good at dealing with the asynchronous Web.
+
+The Web is omnipresent
+----------------------
+
+The Web has taken a very important part of our lives. We're
+connected at all times, when we're on our phone, using our computer,
+passing time using a tablet while in the bathroom... And this
+isn't going to slow down, every single device at home or on us
+will be connected.
+
+All these devices are always connected. And with the number of
+alternatives to give you access to the content you seek, users
+tend to not stick around when problems arise. Users today want
+their applications to be always available and if it's having
+too many issues they just move on.
+
+Despite this, when developers choose a product to use for building
+web applications, their only concern seem to be "Is it fast?",
+and they look around for synthetic benchmarks showing which one
+is the fastest at sending "Hello world" with only a handful
+concurrent connections. Web benchmarks haven't been representative
+of reality in a long time, and are drifting further away as
+time goes on.
+
+What developers should really ask themselves is "Can I service
+all my users with no interruption?" and they'd find that they have
+two choices. They can either hope for the best, or they can use
+Erlang.
+
+Erlang is built for fault tolerance. When writing code in any other
+language, you have to check all the return values and act accordingly
+to avoid any unforeseen issues. If you're lucky, you won't miss
+anything important. When writing Erlang code, you can just check
+the success condition and ignore all errors. If an error happen,
+the Erlang process crashes and is then restarted by a special
+process called a supervisor.
+
+The Erlang developer thus has no need to fear about unhandled
+errors, and can focus on handling only the errors that should
+give some feedback to the user and let the system take care of
+the rest. This also has the advantage of allowing him to write
+a lot less code, and letting him sleep at night.
+
+Erlang's fault tolerance oriented design is the first piece of
+what makes it the best choice for the omnipresent, always available
+Web.
+
+The second piece is Erlang's built-in distribution. Distribution
+is a key part of building a fault tolerant system, because it
+allows you to handle bigger failures, like a whole server going
+down, or even a data center entirely.
+
+Fault tolerance and distribution are important today, and will be
+vital in the future of the Web. Erlang is ready.
+
+Erlang is the ideal platform for the Web
+----------------------------------------
+
+Erlang provides all the important features that the Web requires
+or will require in the near future. Erlang is a perfect match
+for the Web, and it only makes sense to use it to build web
+applications.