How does the computer know whether a binary pattern results in the display of a letter or number?

You (or the compiler you use) have to explicitly tell the computer how to interpret a bit string. So when you write code you'd have to specify "This is a character" or "This is a binary number", high level programming language have functions to make that easier.

I didn't understand how 4 bits can represent 16 values.Could you please explain.Thanks

If we have 4 bits and each can be one of two values, then the number of combinations one can make with 4 bits is equal to 2*2*2*2 = 2^4 = 16.

How does a computer know how to display this information?

The computer know to display the info because it reads digital info in bits, and then outputs and converts those bits into visible things, like letters.

"At 11:47, what are electromechanical transistors?"

it focuses on the interaction of electrical and mechanical systems as a whole and how the two systems interact with eachother.

How would a computer know if 1000011 in a text file represents the number 67 or the letter C?

It nows has a system in it and it travels as a bit it is converted into it when a computer reads it in 1's and 0's and is converted back into the digital form hope it helps🙂

Bits are binary digits (0 and 1)

I dont seem to understand a sequence of bits can anyone explain

When you have more than one bit (or wire), the number of possible values increases. In 1 bit there are two possible values: 1 or 0. In 2 bits, there are four possible values, or combinations: 00, 01, 10, 11. With each additional bit, the number of possible values/combinations goes up by a factor of two.

whenever i see computer specification there written 32 bit 64 bit 128 bit i always wonder what this means

32 bit and 64 bit refer to the addressable memory. A 32 bit computer can only use about 4 GB of RAM, whereas a 64 bit computer can use about 16 exabytes of RAM. 64 bit computers can often do more calculations per second, so they are faster.

Main content

Course: Computers and the Internet > Unit 1

Lesson 1: Bits and bytes

Bits (binary digits)

Google Classroom

Computers store information using bits. A bit (short for "binary digit") stores either the value

0

1

What fits in a bit?

A single bit can only represent two different values. That's not very much, but that's still enough to represent any two-valued state.

Is a lightbulb on or off?

State	Bit
A lightbulb that's off	$0$ ‍
A lightbulb that's on	$1$ ‍

Is a button enabled or disabled?

State	Bit
An enabled button that says "Submit"	$0$ ‍
A disabled button that says "Submit"	$1$ ‍

Is the current time AM or PM?

State	Bit
An alarm clock that says "9:35 AM"	$0$ ‍
An alarm clock that says "9:35 PM"	$1$ ‍

Check your understanding

Consider this settings screen for a Khan Academy user:

Which of the settings can be stored in a single bit?

Sequences of bits

Computers use multiple bits to represent data that is more complex than a simple on/off value.

A sequence of two bits can represent four (

2^{2}

) distinct values:

00

01

10

11

A sequence of three bits can represent eight (

2^{3}

) different values:

000

001

010

011

100

101

110

111

A sequence can represent many things: a number, a character, a pixel. Plus, the same sequence can represent different types of data in different contexts. The sequence

1000011

could represent

67

in a calculator application while also representing the letter "C" in a text file. Learn more in our lessons on Binary numbers and Storing text in binary

Check your understanding

How many different values can four bits represent?

Physical storage

Computers typically store bits using electromechanical transistors which can map electrical signals to either an on or off state. Learn more in our article From electricity to bits or this video on how transistors work.

🙋🏽🙋🏻‍♀️🙋🏿‍♂️Do you have any questions about this topic? We'd love to answer— just ask in the questions area below!

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Jess S
Posted 4 years ago. Direct link to Jess S's post “How does the computer kno...”
How does the computer know whether a binary pattern results in the display of a letter or number?
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- Martin
  Posted 4 years ago. Direct link to Martin's post “You (or the compiler you ...”
  You (or the compiler you use) have to explicitly tell the computer how to interpret a bit string.
  
  So when you write code you'd have to specify "This is a character" or "This is a binary number", high level programming language have functions to make that easier.
  Button navigates to signup page
  (66 votes)
2_Vaz_Jesse
Posted 9 months ago. Direct link to 2_Vaz_Jesse's post “Why did they come to lear...”
Why did they come to learn 1s and 0s? Couldn't they learn our language?
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  It's a computer lil bro
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Shwetha
Posted 4 years ago. Direct link to Shwetha's post “I didn't understand how 4...”
I didn't understand how 4 bits can represent 16 values.Could you please explain.Thanks
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- KLaudano
  Posted 4 years ago. Direct link to KLaudano's post “If we have 4 bits and eac...”
  If we have 4 bits and each can be one of two values, then the number of combinations one can make with 4 bits is equal to 2*2*2*2 = 2^4 = 16.
  Comment on KLaudano's post “If we have 4 bits and eac...”
  (23 votes)
Brayden Weimholt
Posted a year ago. Direct link to Brayden Weimholt's post “How does a computer know ...”
How does a computer know how to display this information?
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(10 votes)
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- liangsamuel3
  Posted 9 months ago. Direct link to liangsamuel3's post “The computer know to disp...”
  The computer know to display the info because it reads digital info in bits, and then outputs and converts those bits into visible things, like letters.
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  (7 votes)
Judepius Ugwuanyi
Posted 4 years ago. Direct link to Judepius Ugwuanyi's post “"At 11:47, what are elect...”
"At
11:47
, what are electromechanical transistors?"
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(8 votes)
Answer
- valeriaacesarr
  Posted 2 years ago. Direct link to valeriaacesarr's post “it focuses on the interac...”
  it focuses on the interaction of electrical and mechanical systems as a whole and how the two systems interact with eachother.
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  (5 votes)
ChrisHatesSchool
Posted a year ago. Direct link to ChrisHatesSchool's post “why is this topic so comp...”
why is this topic so complicated and stressful given the fact that i literally just found out about it today?
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- BenjaminW
  Posted a year ago. Direct link to BenjaminW's post “becus copeters are coplca...”
  becus copeters are coplcated.
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Amily
Posted 9 months ago. Direct link to Amily's post “How would a computer know...”
How would a computer know if 1000011 in a text file represents the number 67 or the letter C?
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- anonymous
  Posted 9 months ago. Direct link to anonymous's post “It nows has a system in i...”
  It nows has a system in it and it travels as a bit it is converted into it when a computer reads it in 1's and 0's and is converted back into the digital form
  hope it helps🙂
  Button navigates to signup page
  (7 votes)
virriobelony80
Posted 10 months ago. Direct link to virriobelony80's post “I dont seem to understand...”
I dont seem to understand a sequence of bits can anyone explain
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Answer
- chromedome
  Posted 10 months ago. Direct link to chromedome's post “When you have more than o...”
  When you have more than one bit (or wire), the number of possible values increases. In 1 bit there are two possible values: 1 or 0. In 2 bits, there are four possible values, or combinations: 00, 01, 10, 11. With each additional bit, the number of possible values/combinations goes up by a factor of two.
  Button navigates to signup page
  (6 votes)
kpendley
Posted a year ago. Direct link to kpendley's post “what are bits”
what are bits
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- tomiwa.
  Posted a year ago. Direct link to tomiwa.'s post “Bits are binary digits (0...”
  Bits are binary digits (0 and 1)
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aniketprasad123
Posted 4 years ago. Direct link to aniketprasad123's post “whenever i see computer s...”
whenever i see computer specification there written
32 bit
64 bit
128 bit

i always wonder what this means
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(3 votes)
Answer
- KLaudano
  Posted 4 years ago. Direct link to KLaudano's post “32 bit and 64 bit refer t...”
  32 bit and 64 bit refer to the addressable memory. A 32 bit computer can only use about 4 GB of RAM, whereas a 64 bit computer can use about 16 exabytes of RAM. 64 bit computers can often do more calculations per second, so they are faster.
  Comment on KLaudano's post “32 bit and 64 bit refer t...”
  (8 votes)