diff --git a/scrollbar.go b/scrollbar.go
index 2f3cdf6..2f71248 100644
--- a/scrollbar.go
+++ b/scrollbar.go
@@ -6,6 +6,8 @@ import "git.tebibyte.media/tomo/tomo/theme"
 import "git.tebibyte.media/tomo/tomo/input"
 import "git.tebibyte.media/tomo/tomo/event"
 
+// Scrollbar is a special type of slider that can control the scroll of any
+// overflowing ContainerBox.
 type Scrollbar struct {
 	tomo.ContainerBox
 	handle     *SliderHandle
@@ -49,14 +51,18 @@ func newScrollbar (orient string) *Scrollbar {
 	return this
 }
 
+// NewVerticalScrollbar creates a new vertical scrollbar.
 func NewVerticalScrollbar () *Scrollbar {
 	return newScrollbar("vertical")
 }
 
+// NewHorizontalScrollbar creates a new horizontal scrollbar.
 func NewHorizontalScrollbar () *Scrollbar {
 	return newScrollbar("horizontal")
 }
 
+// Link assigns this scrollbar to a ContentBox. Closing the returned cookie will
+// unlink it.
 func (this *Scrollbar) Link (box tomo.ContentBox) event.Cookie {
 	this.layout.linked = box
 	this.linkCookie = this.newLinkCookie (