Text represent in computer

How do Text Represented
in Computer?

ComSci Sec3

Analog to digital data

Quick review:
Analog is data that human can receive or understand
Digital is data that computer can receive or understand

All the analog data need to be converted to digital data (binary) to computer understand can process the data.

So, all the text, image, sound, need to be converted to binary too.

How is this done?

Open Ended

Analog is one type of data. Can you please explain what is an analog data?

Multiple Choice

Which ones are included in digital data?

• Binary

• Denary

Multiple Choice

Which data that machine can understand?

• Analog data

• Digital data

Match

Match the data below, which one is digital and which one is analog.

• Text in computer

• Sound from the forest

• 1001101101

Digital

Analog

Binary

• Digital

• Analog

• Binary

Character set

Character set is the tool that computer use to converts text to binary.

There are two main types of character set that a computer can use, they are:

1. ASCII (American Standard Code for Information Interchange).
2. Unicode is a Universal character encoding.

ASCII

ACSII character set represents characters using 7or 8-bit binary number. 7 bit is for ASCII and 8 bit is for extended ASCII.

which can store up to 128 (0-127) characters for ASCII and
256 (0-255) characters for extended ASCII.


Some of the languages has many other character, not only standard letter and it possible to only use ASCII that only has storing for 256 max.

ASCII Table

We can take a look an ASCII table to see how the letter or character are represented.

https://www.ascii-code.com/ASCII

Unicode

Than unicode was invented to make the store is bigger.

Unicode can store around 16 or up to 32-bit which can be contain 2,147,483,647 characters!!!

This means that many more characters can be developed in different alphabets and also symbols can be used, including emoji too!

Unicode

We can take a look an UNICODE table to see how the letter or character are represented.

https://www.ssec.wisc.edu/~tomw/java/unicode.html

https://www.unicode.org/charts/

Open Ended

Please describe what is the meaning of character set.

Open Ended

There are two main types of character set. Can you please mention two of them?

Multiple Choice

Which one is the correct statement for ASCII?

• 7-bit

• 16-bit

Match

Match this following about ASCII and unicode

• 8-bit

• 32-bit

• 7-bit

Extended ASCII

unicode

ASCII

• Extended ASCII

• unicode

• ASCII

Multiple Choice

Refer to the ASCII table, which represent binary 01010111?

• Y

• w

• W

• X

Multiple Choice

Refer to the ASCII table, which represent denary 55?

• 7

• 6

• 8

• A

Multiple Choice

Refer to the ASCII table, what is lowercase "b" in binary?

• 01101000

• 01100010

Multiple Choice

Refer to the unicode table, what is U+004B represent?

• K

• L

• J

​

Thank you!