diff --git a/Hardware/Analogue_and_digital.md b/Hardware/Analogue_and_digital.md
index a19c44d..ab42dc2 100644
--- a/Hardware/Analogue_and_digital.md
+++ b/Hardware/Analogue_and_digital.md
@@ -1,7 +1,7 @@
 ---
 title: Analogue and digital
 categories:
-  - Computer Architecture
+  - Hardware
 tags: [analogue, digital]
 ---
 
diff --git a/Hardware/Binary/Binary_units_of_measurement.md b/Hardware/Binary/Binary_units_of_measurement.md
index ccfe61a..1d34030 100644
--- a/Hardware/Binary/Binary_units_of_measurement.md
+++ b/Hardware/Binary/Binary_units_of_measurement.md
@@ -1,19 +1,40 @@
 ---
 title: Binary units of measurement
 categories:
-  - Computer Architecture
   - Hardware
+  - Mathematics
 tags: [bits, binary]
 ---
 
 # Binary units of measurement
 
-A single place or symbol in a decimal number is called a **digit**. For example the number 34.3 is a number containing three digits. A digit can be any numeral through 0-9.
+A single place or symbol in a decimal number is called a **digit**. For example the number 343 is a number containing three digits. A digit can be any numeral through 0-9.
 
 The equivalent entity in the [binary number system](/Hardware/Binary/The_binary_number_system.md) is the **bit**. For example the binary number 110 has three bits. A bit can only have one of two values in contrast to a digit which can have one of ten values: 0 or 1.
 
 ## Sequences of bits
 
-The informational complexity of digit is much larger than a bit: it can represent one of 10 states whereas a bit can only represent one of two states. Therefore to express greater complexity we work with sequences of bits. Everytime we increase the binary place value of a binary number we are adding to the sequence and increasing the overall complexity of the number by a factor of 2.
+### Informational complexity
+
+The informational complexity of digit is much larger than a bit: it can represent one of 10 states whereas a bit can only represent one of two states.
+
+Consider how much data can be stored in a three digit digital number compared to a three bit binary number. For the decimal number each digit can represent one of ten states, hence the total number of unique states is equal to $3^{10} (59049)$:
+
+```
+001
+002
+003
+...
+010
+011
+012
+013
+...
+```
+
+With the binary number we have $3^{10} (59049)$
+Therefore to express greater complexity we work with sequences of bits.
 
 The standard **base sequence** of bits is called a **byte**. This is a binary number comprising **eight bits**. For example the number `11001110` is a byte equivalent to 206 in decimal.
+
+Every time we add a bit to the sequence of bits comprising a binary number we increase complexity of the number by a factor of 2, i.e. `1, 2, 4, 8, 16, 32, 64, 128` etc.