Add a bit about slides

src/SUMMARY.md

@@ -1,6 +1,6 @@
 # Summary
 
-- [Grezi](./chapter_1.md)
+- [Grezi](./index.md)
 - [Viewboxes](./viewboxes.md)
 - [Objects](./objects.md)
   - [Paragraphs](./paragraphs.md)
@@ -9,3 +9,4 @@
 - [Slides](./slides.md)
   - [Functions](./functions.md)
 - [Actions](./actions.md)
+- [Special Language Server Functions](./lsp.md)

src/lsp.md

@@ -0,0 +1 @@
+# Special Language Server Functions

src/slides.md

@@ -1,3 +1,13 @@
 # Slides
 
+Slides describe which objects should go on the screen, where those objects are coming from, and where they're going.
 
+A slide looks like this
+
+```
+{
+    TitleImage: ViewBox[0]....,
+    Title: ViewBox[0]__..,
+    Subtitle: ViewBox[1]__..,
+}[]
+```