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Bharath Muppa for Entangled Cognition

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What is a bit?

All over Computer science, whomever you talk with, they keep saying about data.

  • To store Data.
  • Compute Data.
  • Send/Request Data over Network.
  • Predictions on Data.
  • Represent Data.

The fundamental unit of this data is called a bit(B inary dig IT ).

The State of Bit is always binary which means it can represent two values 0 or 1, true or false, charge presence or charge absence.

Observe the gif once and start assuming there will be some kind of boxes in a computer that stores each bit.

Alt Text


📢 Let's ask Ourself few interesting questions

  1. I have understood there will be some kind of box that stores the current charge but what is this made of?
  2. Why that box use Binary System instead of others like decimal or Hexa?
  3. What are the different memory units?

1. What is this Bit made of ?

A Bit is an electric circuit with transistors and capacitors arranged in a specific way.

Transistors are switches, but a special kind of Transistors called MOSFETS are used in volatile memories (SSD, HDD) and MOSFETS combined capacitors are used in RAM.

We will discuss the above concepts in detail across this series, Which will give you a clear picture of the inner workings of the Integrated circuit and memory architectures.

Topics to learn

  • Memory cell architecture
  • Volatile and Non-Volatile Memories.
  • NAND flash vs NOR Flash
  • Gates

2. Why Binary ?

Introduction to Number systems 🧮

We, Humans, are very much fond of the decimal system and important question is we never know how we used to it. Instead of long history, just think we used to it because of Egyptian and indus-valley civilizations.

In the decimal (base-10) numbering system, the digits are the elements of the set {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}.

Eg: 1024.8 - {4 is one's digit, 2 is at ten's digit,0 is in hundreds digit and, 1 is at thousands digit,8 is at tenths digit}

In the binary number system, the digits are the elements of the set {0, 1}. This system is used by computers because the two digits can represent the logic low and high states. The term "binary digit" is compressed to " bit " in computer parlance.

Eg: 1,0,11,00,10,01

Computer Scientists

There was a time when computer scientists have to choose a number system and opt for a binary system because of vast study on those systems by above great personalities(George Bool and Leibniz) and also due to the limitations in electronics at that point of time.

3. Different memory units.

Now we can use the above acquired knowledge to build bytes, MegaBytes, GigaBytes and so on.

Storage Unit Possible No of states
1 memory unit 1 bit 21
4b 1 Nibble 24
8b 1 Byte 28
1024B 1 KiloByte 28192
1024KB 1 MegaByte 28388608
1024MB 1 GigaByte 28589934592
1024GB 1 TeraByte 28796093022208
1024TB 1 PetaByte 29007199254740992
1024PB 1 ExaByte 29223372036854776000
1024EB 1 ZettaByte 29.44473296573929e+21
1024ZB 1 YottaByte 29.671406556917033e+24
1024YB 1 BrontoByte 2Huge number
1024BB 1 GeopByte 2Even Huge number

Note:
There is a difference in representing bit(b) and Byte(B)
whenever your network provider says your download speed is 80Mbps.
it doesn't mean 80 MegaBytes per second, it means 80 Megabits per second that counts to 10 MBps.
That's how they fool ordinary people.🤐

References

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