docs: Adding placeholder pages for various tools.

 * Analog tooling
   - Generators BAG, FASoC, etc
   - Manual tools KLayout, Magic, Innovus, etc

 * Digital tooling
   - Cadence Innovus
   - OpenROAD

 * Simulation tooling
   - ngspice
   - Cadence Spectre

Signed-off-by: Tim 'mithro' Ansell <me@mith.ro>
diff --git a/docs/analog.rst b/docs/analog.rst
new file mode 100644
index 0000000..676e16b
--- /dev/null
+++ b/docs/analog.rst
@@ -0,0 +1,13 @@
+Analog Design
+=============
+
+.. toctree::
+    :caption: Analog Design
+    :name: analog
+
+    With Cadence Virtuoso <analog/virtuoso>
+    With MAGIC <analog/magic>
+    With Klayout <analog/klayout>
+    With Berkeley Analog Generator (BAG) <analog/bag>
+    With FASoC <analog/fasoc>
+    With your design flow? <analog/new>
diff --git a/docs/analog/bag.rst b/docs/analog/bag.rst
new file mode 100644
index 0000000..a8b8297
--- /dev/null
+++ b/docs/analog/bag.rst
@@ -0,0 +1,2 @@
+TODO: analog/bag
+================
diff --git a/docs/analog/fasoc.rst b/docs/analog/fasoc.rst
new file mode 100644
index 0000000..c69f7f4
--- /dev/null
+++ b/docs/analog/fasoc.rst
@@ -0,0 +1,2 @@
+TODO: analog/fasoc
+==================
diff --git a/docs/analog/klayout.rst b/docs/analog/klayout.rst
new file mode 100644
index 0000000..6ca919d
--- /dev/null
+++ b/docs/analog/klayout.rst
@@ -0,0 +1,2 @@
+TODO: analog/klayout
+====================
diff --git a/docs/analog/magic.rst b/docs/analog/magic.rst
new file mode 100644
index 0000000..8e8d6b5
--- /dev/null
+++ b/docs/analog/magic.rst
@@ -0,0 +1,2 @@
+TODO: analog/magic
+==================
diff --git a/docs/analog/new.rst b/docs/analog/new.rst
new file mode 100644
index 0000000..f9403bc
--- /dev/null
+++ b/docs/analog/new.rst
@@ -0,0 +1,2 @@
+TODO: analog/new
+================
diff --git a/docs/analog/virtuoso.rst b/docs/analog/virtuoso.rst
new file mode 100644
index 0000000..0b862ee
--- /dev/null
+++ b/docs/analog/virtuoso.rst
@@ -0,0 +1,2 @@
+TODO: analog/virtuoso
+=====================
diff --git a/docs/digital.rst b/docs/digital.rst
new file mode 100644
index 0000000..0b66880
--- /dev/null
+++ b/docs/digital.rst
@@ -0,0 +1,10 @@
+Digital Design
+==============
+
+.. toctree::
+    :caption: Digital Design
+    :name: digital
+
+    With Cadence Innovus <digital/innovus>
+    With OpenROAD <digital/openroad>
+    With your design flow? <digital/new>
diff --git a/docs/digital/innovus.rst b/docs/digital/innovus.rst
new file mode 100644
index 0000000..3977f32
--- /dev/null
+++ b/docs/digital/innovus.rst
@@ -0,0 +1,2 @@
+TODO: digital/innovus
+=====================
diff --git a/docs/digital/new.rst b/docs/digital/new.rst
new file mode 100644
index 0000000..9a03b37
--- /dev/null
+++ b/docs/digital/new.rst
@@ -0,0 +1,2 @@
+TODO: digital/new
+=================
diff --git a/docs/digital/openroad.rst b/docs/digital/openroad.rst
new file mode 100644
index 0000000..40b64b4
--- /dev/null
+++ b/docs/digital/openroad.rst
@@ -0,0 +1,2 @@
+TODO: digital/openroad
+======================
diff --git a/docs/index.rst b/docs/index.rst
index 97d18b1..013bbef 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -3,21 +3,29 @@
 .. toctree::
     :hidden:
 
-    Design Rules <rules>
-
-    contents
-
     versioning
     Current Status <status>
     known_issues
 
-    contributing
-    partners
+    Design Rules <rules>
+
+    contents
+
+    analog
+    digital
+    sim
 
     Python API <python-api/index>
 
+    previous
     glossary
 
+    contributing
+    partners
+
+
+
+
 Welcome to SkyWater SKY130 PDK's documentation!
 ===============================================
 
diff --git a/docs/sim.rst b/docs/sim.rst
new file mode 100644
index 0000000..10891b2
--- /dev/null
+++ b/docs/sim.rst
@@ -0,0 +1,17 @@
+Simulation
+==========
+
+.. toctree::
+    :caption: Simulation
+    :name: sim
+
+    With Cadence Spectre <sim/spectre>
+    With ngspice <sim/ngspice>
+    With your design flow? <analog/new>
+
+.. todo::
+
+    The SkyWater SKY130 PDK provides simulation two types of simulation models.
+    :term:`Spectre models` for usage with :term:`Cadence Spectre` and
+    :term:`Spice models` which are compatible with popular open source spice
+    simulators like :term:`ngspice`.
diff --git a/docs/sim/ngspice.rst b/docs/sim/ngspice.rst
new file mode 100644
index 0000000..0136168
--- /dev/null
+++ b/docs/sim/ngspice.rst
@@ -0,0 +1,2 @@
+TODO: sim/ngspice
+=================
diff --git a/docs/sim/spectre.rst b/docs/sim/spectre.rst
new file mode 100644
index 0000000..5090786
--- /dev/null
+++ b/docs/sim/spectre.rst
@@ -0,0 +1,2 @@
+TODO: sim/spectre
+=================
diff --git a/docs/sim/spice.rst b/docs/sim/spice.rst
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/docs/sim/spice.rst