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+# Course Scheduler
+This is an Elm-based implementation of Homework 4c for Human Computer Interaction.
+Elm is a functional programming language that __compiles to JavaScript__.
+
+## Directory structure
+* `src/` contains the Elm source code for the application.
+  * `Model.elm` contains descriptions of the data structures used
+    in the project.
+  * `View.elm` contains the code to actually display the HTML page.
+  * `Decode.elm` contains code to translate the JSON file given to
+    us into Elm data structures.
+* `scss/` contains the (Sassy) CSS that was used to style the project.
+* `dist/` contains the compiled Elm and SCSS code, so that you don't
+  need to install the Elm compiler or anything of that sort.
+
+## Running
+Open `dist/index.html` (run `python`'s web server command in `dist`, other than that, business as usual).
+
+## Info
+In Elm, HTML is build using functions in the language I don't write HTML per se, but
+rather, call functions that build the correspoding HTML elements. For example,
+the following code:
+
+```html
+<tr class="hello">
+    <td>Hello</td>
+    <td>Hello</td>
+</tr>
+```
+
+Looks like the following in Elm:
+
+```Elm
+tr [ class "hello" ]
+    [ td [] [ text "Hello" ]
+    , td p] [ text "Hello" ]
+    ]
+```
+
+However, the Elm-based view of writing HTML allows for the full
+power of the programming language in this "template" section.
+For instance, I can write the following:
+
+```Elm
+viewAddedBubble : Bool -> List (Html Msg)
+viewAddedBubble b = if b then [ span [ class "bubble", class "color-green" ] [ checkIcon, text "Added!" ] ] else []
+```
+
+This defines a function that returns an HTML element (a green "Added!" button)
+if a boolean `b` is true, and otherwise returns an empty list (thus, the "added" button is absent).
+Thus, the same language is used for actually _rendering_ the page as is used for implementing
+its logic.
+
+Elm is __reactive programming in its purest form__: the language is built around the idea of FRP
+(functional reactive programming). Elm code consists of three main things:
+
+* The model (the current state of the application, including all its data)
+* The view (the HTML that is built from the current model / state)
+* The update (when events happen, i.e. a user clicks a button, the update changes the state accordingly,
+  and the view is updated)