Binary numbers like '0110', or '00100101' are seen very often in all contexts. What are the leading (left hand side) zeroes for? Why did the writer not write '110' and '100101', respectively?
Leading zeroes in binary usually indicate the bit length of the data type.
For example, the number
110 represented in a 4 bit data type would be
Even if there is no data type specified, it's sometimes common to pad your binary numbers to the next power of 2. For example,
10111 of size 5 should be padded to 8 $(2^3)$ as