Begin document kernel lifecycle

docs/advanced-features/autodiscovery.md

@@ -38,3 +38,47 @@ as a singleton into the application service container.
 At this point you might be wondering why we're talking about the kernel when this article is about autodiscovery.
 Well, as you'll see in just a moment, the kernel is responsible for initiating the autodiscovery process.
 The kernel is also where the discovered data is stored in memory, so it's important to understand how it works.
+
+### The kernel lifecycle
+
+Now that we know the role of the HydeKernel, let's take a look at its lifecycle. The kernel is "lazy-booted", meaning
+that the all the heavy lifting only happens when you actually need it. Once booted, the kernel data will stay in memory
+until the application is terminated.
+
+The kernel data is primarily stored in three collections that get generated during the kernel's boot process.
+Let's take a look at the kernel's boot method to see how this works.
+
+```php
+public function boot(): void
+{
+    $this->booted = true;
+
+    $this->files = FileCollection::boot($this);
+    $this->pages = PageCollection::boot($this);
+    $this->routes = RouteCollection::boot($this);
+}
+```
+
+Here you'll see that we boot the three collections. This is where all the autodiscovery magic happens!
+We'll take a closer look at each of these in a second, but first, here's how the "lazy-booting" works.
+
+```php
+// This will boot the kernel if it hasn't been booted yet
+protected function needsToBeBooted(): void
+{
+    if (! $this->booted) {
+        $this->boot();
+    }
+}
+
+// And here's an example of how it's used
+public function pages(): PageCollection
+{
+    $this->needsToBeBooted();
+
+    return $this->pages;
+}
+```
+
+Yeah, it's really unglamorous I know. But it works! Having it like this will ensure that any time you call `Hyde::pages()`,
+that underlying collection will always have been booted and be ready to use.