diff --git a/README.md b/README.md
index cb093c1..cf57e12 100644
--- a/README.md
+++ b/README.md
@@ -23,9 +23,9 @@ Unplug your Keybow 2040's USB-C cable, press and hold the button on the top edge
 of Keybow 2040 while plugging the USB-C cable back into your computer to mount
 it as a drive (it should show up as `RPI-RP2` or something similar).
 
-Drag and drop the `xxxxxxxx.uf2` file that you downloaded onto the drive and it
-should reboot and load the CircuitPython firmware. The drive should now show up
-as `CIRCUITPY`.
+Drag and drop the `adafruit-circuitpython-pimoroni_keybow2040-en_US-XXXXX.uf2`
+file that you downloaded onto the drive and it should reboot and load the 
+CircuitPython firmware. The drive should now show up as `CIRCUITPY`.
 
 The Adafruit IS31FL3731 LED driver library for CircuitPython is a prequisite for
 this Keybow 2040 library, so you'll need to download it from GitHub at the link
@@ -41,4 +41,238 @@ Pick one of the [examples](examples) (I'd suggest the
 [reactive.press.py](examples/reactive-press.py) example to begin), copy the 
 code, and save it in the `code.py` file on your `CIRCUITPY` drive using your 
 favourite text editor. As soon as you save the `code.py` file, or make any other
-changes, then it should load up and run the code!
\ No newline at end of file
+changes, then it should load up and run the code!
+
+## Basics
+
+## Imports and setup
+
+All of your programs will need to start with the following:
+
+```
+import board
+from keybow2040 import Keybow2040
+
+i2c = board.I2C()
+keybow = Keybow2040(i2c)
+```
+
+First, this imports the `board` module which contains all of the pin objects for
+the Keybow 2040 board, including `board.I2C`, a quick way to set up the I2C bus, 
+which is needed for the IS31FL3731 LED driver library used in this Keybow 2040
+library.
+
+The `Keybow2040()` class, imported from the `keybow2040` module, is instantiated
+and passed the i2c bus object. Instantiating this sets up all of the pins, keys,
+and LEDs, and provides access to all of the attributes and methods associated 
+with it.
+
+## The Keybow class
+
+The Keybow class exposes a number of handy attributes and methods. The main one
+you'll be interested in is the `.keys` attribute, which is a list of `Key` 
+class instances, one for each key.
+
+```
+keys = keybow.keys
+```
+
+The indices of the keys in that list correspond to their position on the keypad,
+staring from the bottom left corner (when the USB connector is at the top), 
+which is key 0, going upwards in columns, and ending at the top right corner,
+which is key 15.
+
+More about the `Key` class later...
+
+A **super** important method of the `Keybow` class is `.update()` method. It 
+updates all of the keys, key states, and other attributes like the time of the
+last key press, and sleep state of the LEDs.
+
+**You need to call this method on your `Keybow` class at the very start of each
+iteration of your program's main loop, as follows:**
+
+```
+while True:
+    keybow.update()
+```
+
+## An interlude on timing!
+
+Another **super** important thing is **not to include any `time.sleep()`s in 
+your main loop!** Doing so will ruin the latency and mean that you'll miss key
+press events. Just don't do it.
+
+If you need introduce timed events, then you have to go about it in a slightly
+(!!) roundabout fashion, by using `time.monotonic()` a constantly incremented
+count of seconds elapsed, and use it to check the time elapsed since your last
+event, for example:
+
+```
+time_interval = 10
+
+# An event just happened!
+
+time_last_fired = time.monotonic()
+time_elapsed = 0
+
+# ... some iterations later
+
+time_elapsed = time.monotonic() - time_last_fired
+
+if time_elapsed > time_interval:
+    # Fire your event again!
+```
+
+There's a handy `keybow.time_of_last_press` attribute that allows you to quickly
+check if a certain amount of time has elapsed since any key press, and that
+attribute gets updated every time `keybow.update()` is called.
+
+## Key presses
+
+There are a few ways that you can go about detecting key presses, some
+global methods on the `Keybow` class instance, and some on the `Key` class
+instances themselves.
+
+### Keybow class methods for detecting presses and key states
+
+`keybow.get_states()` will return a list of the state of all of the keys, in 
+order, with a state of `0` being not pressed, and `1` being pressed. You can
+then loop through that list to do whatever you like.
+
+`keybow.get_pressed()` will return a list of the key numbers (indices in the 
+list of keys) that are currently pressed. If you only care about key presses,
+then this is an efficient way to do things, especially since you have all the
+key numbers in a list.
+
+`keybow.any_pressed()` returns a Boolean (`True`/`False`) that tells you whether
+any keys are currently being pressed. Handy if you want to attach a behaviour to
+all of the keys, which this is effectively a proxy for.
+
+`keybow.none_pressed()` is similar to `.any_pressed()`, in that it returns a 
+Boolean also, but... you guessed it, it returns `True` if no keys are being
+pressed, and `False` if any keys are pressed.
+
+### Key class methods for detecting key presses
+
+If we want to check whether key 0 is pressed, we can do so as follows:
+
+```
+keys = keybow.keys()
+
+if keys[0].pressed:
+    # Do something!
+```
+
+The `.pressed` attribute returns a Boolean that is `True` if the key is pressed
+and `False` if it is not pressed.
+
+`key.state` is another way to check the state of a key. It will equal `1` if the
+key is pressed and `0` if it is not pressed.
+
+If you want to attach an additional behaviour to your key, you can use 
+`key.held` to check if a key is being key rather than being pressed and released
+quickly. It returns `True` if the key is held and `False` if it is not.
+
+The default hold time (after which `key.held` is `True`) for all of the keys is
+0.75 seconds, but you can change `key.hold_time` to adjust this to your liking, 
+on a per key basis.
+
+This means that we could extend the example above to be:
+
+```
+keys = keybow.keys()
+
+if keys[0].pressed:
+    # Do something!
+
+if keys[0].held:
+    # Do something else!
+```
+
+## LEDs!
+
+LEDs can be set either globally for all keys, using the `Keybow` class instance,
+or on a per-key basis, either through the `Keybow` class, or using a `Key` class
+instance.
+
+To set all of the keys to the same colour, you can use the `.set_all()` method
+of the `Keybow` class, to which you pass three 0-255 integers for red, green, 
+and blue. For example, to set all of the keys to magenta:
+
+```
+keybow.set_all(255, 0, 255)
+```
+
+To set an individal key through your `Keybow` class instance, you can do as
+follows, to set key 0 to white:
+
+```
+keybow.set_led(0, 255, 255, 255)
+```
+
+To set the colour on the key itself, you could do as follows, again to set key
+0 to white:
+
+```
+keybow.keys[0].set_led(255, 255, 255)
+```
+
+A key retains its RGB value, even if it is turned off, so once a key has its 
+colour set with `key.rgb = (255, 0, 0)` for example, you can turn it off using
+`key.led_off()` or even `key.set_led(0, 0, 0)` and then when you turn it back on
+with `key.led_on()`, then it will still be red when it comes back on.
+
+As a convenience, and to avoid having to check `key.lit`, there is a 
+`key.toggle_led()` method that will toggle the current state of the key's LED 
+(on to off, and _vice versa_).
+
+There's a handy `hsv_to_rgb()` function that can be imported from the 
+`keybow2040` module to convert an HSV colour (a tuple of floats from 0.0 to 1.0)
+to an RGB colour (a tuple of integers from 0 to 255), as follows:
+
+```
+from keybow2040 import hsv_to_rgb
+
+h = 0.5  # Hue
+s = 1.0  # Saturation
+v = 1.0  # Value
+
+r, g, b = hsv_to_rgb(h, s, v)
+```
+
+## Attaching functions to keys with decorators
+
+There are three decorators that can be attached to functions to link that 
+function to, i) a key press, ii) a key release, or iii) a key hold.
+
+Here's an example of how you could attach a decorator to a function that lights
+up that key yellow when it is pressed, turns all of the LEDs on when held, and 
+turns them all off when released:
+
+```
+import board
+from keybow2040 import Keybow2040
+
+i2c = board.I2C()
+keybow = Keybow2040(i2c)
+keys = keybow.keys
+
+key = keys[0]
+rgb = (255, 255, 0)
+key.rgb = rgb
+
+@keybow.on_press(key)
+def press_handler(key):
+    key.led_on()
+
+@keybow.on_release(key)
+def release_handler(key):
+    keybow.set_all(0, 0, 0)
+
+@keybow.on_hold(key)
+def hold_handler(key):
+    keybow.set_all(*rgb)
+
+while True:
+    keybow.update()
+```
\ No newline at end of file
diff --git a/examples/colour-picker.py b/examples/colour-picker.py
index 5f1a826..5e36e86 100644
--- a/examples/colour-picker.py
+++ b/examples/colour-picker.py
@@ -7,39 +7,11 @@
 
 # Drop the keybow2040.py file into your `lib` folder on your `CIRCUITPY` drive.
 
-import time
 import board
-import random
-from keybow2040 import Keybow2040, number_to_xy
+from keybow2040 import Keybow2040, number_to_xy, hsv_to_rgb
 
 MODIFIER_KEY = 0
 
-def hsv_to_rgb(h, s, v):
-    # Convert an HSV (0.0-1.0) colour to RGB (0-255)
-    if s == 0.0:
-        rgb = [v, v, v]
-    
-    i = int(h * 6.0)
-
-    f = (h*6.)-i; p,q,t = v*(1.-s), v*(1.-s*f), v*(1.-s*(1.-f)); i%=6
-    
-    if i == 0:
-        rgb = [v, t, p]
-    if i == 1:
-        rgb = [q, v, p]
-    if i == 2:
-        rgb = [p, v, t]
-    if i == 3:
-        rgb = [p, q, v]
-    if i == 4:
-        rgb = [t, p, v]
-    if i == 5:
-        rgb = [v, p, q]
-
-    rgb = [int(c * 255) for c in rgb]
-
-    return rgb
-
 # Set up Keybow
 i2c = board.I2C()
 keybow = Keybow2040(i2c)
diff --git a/examples/decorators.py b/examples/decorators.py
index 091b32e..39daaa9 100644
--- a/examples/decorators.py
+++ b/examples/decorators.py
@@ -7,9 +7,7 @@
 
 # Drop the keybow2040.py file into your `lib` folder on your `CIRCUITPY` drive.
 
-import time
 import board
-import random
 from keybow2040 import Keybow2040
 
 # Set up Keybow
diff --git a/examples/midi-arp.py b/examples/midi-arp.py
index 1d39594..d75fa1c 100644
--- a/examples/midi-arp.py
+++ b/examples/midi-arp.py
@@ -15,7 +15,6 @@
 
 import time
 import board
-import random
 from keybow2040 import Keybow2040
 
 import usb_midi
diff --git a/examples/midi-keys.py b/examples/midi-keys.py
index 44fc56e..a05eaf6 100644
--- a/examples/midi-keys.py
+++ b/examples/midi-keys.py
@@ -14,7 +14,6 @@
 
 import time
 import board
-import random
 from keybow2040 import Keybow2040
 
 import usb_midi
diff --git a/examples/rainbow.py b/examples/rainbow.py
index b9fda21..261a1e8 100644
--- a/examples/rainbow.py
+++ b/examples/rainbow.py
@@ -6,37 +6,9 @@
 
 # Drop the keybow2040.py file into your `lib` folder on your `CIRCUITPY` drive.
 
-import time
 import math
 import board
-from keybow2040 import Keybow2040, number_to_xy
-
-
-def hsv_to_rgb(h, s, v):
-    # Convert an HSV (0.0-1.0) colour to RGB (0-255)
-    if s == 0.0:
-        rgb = [v, v, v]
-    
-    i = int(h * 6.0)
-
-    f = (h*6.)-i; p,q,t = v*(1.-s), v*(1.-s*f), v*(1.-s*(1.-f)); i%=6
-    
-    if i == 0:
-        rgb = [v, t, p]
-    if i == 1:
-        rgb = [q, v, p]
-    if i == 2:
-        rgb = [p, v, t]
-    if i == 3:
-        rgb = [p, q, v]
-    if i == 4:
-        rgb = [t, p, v]
-    if i == 5:
-        rgb = [v, p, q]
-
-    rgb = (int(c * 255) for c in rgb)
-
-    return rgb
+from keybow2040 import Keybow2040, number_to_xy, hsv_to_rgb
 
 # Set up Keybow
 i2c = board.I2C()
diff --git a/keybow2040.py b/keybow2040.py
index b68264b..0c51147 100755
--- a/keybow2040.py
+++ b/keybow2040.py
@@ -420,4 +420,30 @@ def number_to_xy(number):
     x = number % 4
     y = number // 4
 
-    return (x, y)
\ No newline at end of file
+    return (x, y)
+
+def hsv_to_rgb(h, s, v):
+    # Convert an HSV (0.0-1.0) colour to RGB (0-255)
+    if s == 0.0:
+        rgb = [v, v, v]
+    
+    i = int(h * 6.0)
+
+    f = (h*6.)-i; p,q,t = v*(1.-s), v*(1.-s*f), v*(1.-s*(1.-f)); i%=6
+    
+    if i == 0:
+        rgb = [v, t, p]
+    if i == 1:
+        rgb = [q, v, p]
+    if i == 2:
+        rgb = [p, v, t]
+    if i == 3:
+        rgb = [p, q, v]
+    if i == 4:
+        rgb = [t, p, v]
+    if i == 5:
+        rgb = [v, p, q]
+
+    rgb = (int(c * 255) for c in rgb)
+
+    return rgb
\ No newline at end of file