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+# Overview
+
+Inspired by [The Elm Architecture], Iced expects you to split user interfaces
+into four different concepts:
+
+* __State__ — the state of your application
+* __Messages__ — user interactions or meaningful events that you care
+ about
+* __View logic__ — a way to display your __state__ as widgets that
+ may produce __messages__ on user interaction
+* __Update logic__ — a way to react to __messages__ and update your
+ __state__
+
+We can build something to see how this works! Let's say we want a simple counter
+that can be incremented and decremented using two buttons.
+
+We start by modelling the __state__ of our application:
+
+```rust
+#[derive(Default)]
+struct Counter {
+ value: i32,
+}
+```
+
+Next, we need to define the possible user interactions of our counter:
+the button presses. These interactions are our __messages__:
+
+```rust
+#[derive(Debug, Clone, Copy)]
+pub enum Message {
+ Increment,
+ Decrement,
+}
+```
+
+Now, let's show the actual counter by putting it all together in our
+__view logic__:
+
+```rust
+use iced::widget::{button, column, text, Column};
+
+impl Counter {
+ pub fn view(&self) -> Column<Message> {
+ // We use a column: a simple vertical layout
+ column![
+ // The increment button. We tell it to produce an
+ // `Increment` message when pressed
+ button("+").on_press(Message::Increment),
+
+ // We show the value of the counter here
+ text(self.value).size(50),
+
+ // The decrement button. We tell it to produce a
+ // `Decrement` message when pressed
+ button("-").on_press(Message::Decrement),
+ ]
+ }
+}
+```
+
+Finally, we need to be able to react to any produced __messages__ and change our
+__state__ accordingly in our __update logic__:
+
+```rust
+impl Counter {
+ // ...
+
+ pub fn update(&mut self, message: Message) {
+ match message {
+ Message::Increment => {
+ self.value += 1;
+ }
+ Message::Decrement => {
+ self.value -= 1;
+ }
+ }
+ }
+}
+```
+
+And that's everything! We just wrote a whole user interface. Let's run it:
+
+```rust
+fn main() -> iced::Result {
+ iced::run("A cool counter", Counter::update, Counter::view)
+}
+```
+
+Iced will automatically:
+
+ 1. Take the result of our __view logic__ and layout its widgets.
+ 1. Process events from our system and produce __messages__ for our
+ __update logic__.
+ 1. Draw the resulting user interface.
+
+Read the [book], the [documentation], and the [examples] to learn more!
+
+[book]: https://book.iced.rs/
+[documentation]: https://docs.rs/iced/
+[examples]: https://github.com/iced-rs/iced/tree/master/examples#examples
+[The Elm Architecture]: https://guide.elm-lang.org/architecture/