LSB

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: Least significant bit
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MSB

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: Most significant bit

Bit Numbering:

There are 2 common bit numbering schemes LSB0 nad and LSB1:

LSB0:

Starts with LSB as 0 goes to MSB as 7

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Starts with LSB as 1 goes to MSB as 8.

In other words:

• A bit has two values (on or off, 1 or 0)
• A byte is a sequence of 8 bits:
  • The "leftmost" bit in a byte is the biggest. So, the binary sequence 00001001 is the decimal number 9. 00001001 = (2³ + 2⁰ = 8 + 1 = 9).
  • For LSB0, Bits are numbered from right-to-left. Bit 0 is the rightmost and the smallest; bit 7 is leftmost and the largest
  • For LSB1, Bits are numbered from right-to-left. Bit 1 is the rightmost and the smallest; bit 8 is leftmost and the largest

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Byte Numbering:

Many will just count Bytes bytes starting from the Left left to Rightright. You will see people start with 1 or 0. So, in the following example,   02 is the first byte and could be referred to as Byte 0 or Byte 1. A C programer -programmer would probably refer to it as Byte 0 because that is the way memory is addressed in C. Someone that who is not a C-programmer might call it Byte 1.  Byte 0 is probably more well-accepted.

As for how to store a number or data in such a system, you have to know if it is stare Big Endian or Little Endian. 

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