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+This is an overview of the major events in the history of our Layers infrastructure.
+
+- iPhone released in July 2007 (Built on a toolkit called LayerKit)
+
+- Core Animation (October 2007) LayerKit was publicly renamed to OS X 10.5
+
+- Webkit CSS 3d transforms (July 2009)
+
+- Original layers API (March 2010) Introduced the idea of a layer manager that
+  would composite. One of the first use cases for this was hardware accelerated
+  YUV conversion for video.
+
+- Retained layers (July 7 2010 - Bug 564991)
+This was an important concept that introduced the idea of persisting the layer
+content across paints in gecko controlled buffers instead of just by the OS. This introduced
+the concept of buffer rotation to deal with scrolling instead of using the
+native scrolling APIs like ScrollWindowEx
+
+- Layers IPC (July 2010 - Bug 570294)
+This introduced shadow layers and edit lists and was originally done for e10s v1
+
+- 3d transforms (September 2011 - Bug 505115)
+
+- OMTC (December 2011 - Bug 711168)
+This was prototyped on OS X but shipped first for Fennec
+
+- Tiling v1 (April 2012 - Bug 739679)
+Originally done for Fennec.
+This was done to avoid situations where we had to do a bunch of work for
+scrolling a small amount. i.e. buffer rotation.  It allowed us to have a
+variety of interesting features like progressive painting and lower resolution
+painting.
+
+- C++ Async pan zoom controller (July 2012 - Bug 750974)
+The existing APZ code was in Java for Fennec so this was reimplemented.
+
+- Streaming WebGL Buffers (February 2013 - Bug 716859)
+Infrastructure to allow OMTC WebGL and avoid the need to glFinish() every
+frame.
+
+- Compositor API (April 2013 - Bug 825928)
+The planning for this started around November 2012.
+Layers refactoring created a compositor API that abstracted away the differences between the
+D3D vs OpenGL. The main piece of API is DrawQuad.
+
+- Tiling v2 (Mar 7 2014 - Bug 963073)
+Tiling for B2G. This work is mainly porting tiled layers to new textures,
+implementing double-buffered tiles and implementing a texture client pool, to
+be used by tiled content clients.
+
+ A large motivation for the pool was the very slow performance of allocating tiles because
+of the sync messages to the compositor.
+
+ The slow performance of allocating was directly addressed by bug 959089 which allowed us
+to allocate gralloc buffers without sync messages to the compositor thread.
+
+- B2G WebGL performance (May 2014 - Bug 1006957, 1001417, 1024144)
+This work improved the synchronization mechanism between the compositor
+and the producer.
+