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docs/tut/crash-course/4-source.md

@@ -25,10 +25,13 @@ count(count() + 1) -- increment source by 1
 Below is an example of a stateful counter component.
 
 ```lua
-local function Counter()
+local function Counter(props: { Position: UDim2 })
     local count = source(0)
 
     return create "TextButton" {
+        Position = props.Position,
+        Size = UDim2.new(200, 50),
+
         Text = count,
 
         Activated = function()
@@ -38,21 +41,22 @@ local function Counter()
 end
 ```
 
+Each call of `Counter {}` will create a new counter element, each with their own
+independent count.
+
 Vide detects when you assign a function to a property. This is known
 as *binding* and doing so will cause the property to *automatically* update
 whenever a source in that function is updated, by rerunning the function and
 assigning its return value. You can only bind non-event
 properties, otherwise the function is connected as the event callback.
 
-You as the programmer do not have to worry about manually updating variables or
-UI instances, you can just focus on defining how the data maps to UI and
-everything will update when changes occur.
+This allows you as the programmer to not need to manually update GUI as the state
+of your program changes. You just define how the data maps to UI, and Vide's
+reactive system will surgically update any properties depending on sources that
+are changed.
 
-Each call of `Counter {}` will create a new counter element, each with their own
-independent count.
-
-Since sources are just functions, you can pass an external source to a component
-like so:
+Since sources are just functions, you can also pass external sources to
+components like so:
 
 ```lua
 local function Text(p: {