Section 7.3

Learning Goals

• Students will define bit and byte.

• Students will explain the relationship between groups of bits and the concept of abstraction.

• DAT-1.A.2: Computing devices represent data digitally, meaning that the lowest-level components of any value are bits.

• DAT-1.A.3: Bit is shorthand for binary digit and is either 0 or 1.

• DAT-1.A.4: A byte is 8 bits.

Objectives and General Description

The way a computer represents data internally is different from the way the data are interpreted and displayed for the user. Programs are used to translate data into a representation more easily understood by people.  In this section students will learn about the smallest unit of data on a computer, the bit, and bits can be grouped together to represent complex data.  Students will also discuss the concept of abstraction in computing as it relates to hiding the complex binary data by displaying the data in a form that is more user friendly.

Activities

Activity 7.3.1 (55 minutes)

1. Have students watch How Computers Work:  Binary & Data.  This can be done at the beginning of class or as a flipped assignment.  

2. While watching the video, have students make their own guided notes for the video.

3. After the video, have students get into small groups.  Each group answers one of the following questions

   • Why do we not deal directly with 1's and 0's?

   • How do you store or represent information using electricity?

   • What do you need to represent more complex information?

   • What types of information can be represented with 1's and 0's?

   • What is a non-computer example of a binary state?

   • Why is binary important to computing?

4. Using a jigsaw technique, rearrange the groups so that each group has an "expert" on each question.  That expert will share the answer to their question and explain why that answer is correct.

5.  Class discussion:  Ask for a summary of the questions & responses. Highlight the concept of abstraction and how it relates to data.  Also emphasize that the more bits you have, the more complex data you can represent.  

6. Give students 10 minutes to read and explore the relationship between Braille and data representation.  With a partner, students should try to determine the highest number of dot combinations for different numbers of dots (tool is in the middle of the webpage).  Challenge students to find the mathematical relationship.

7. Discuss:  what is the relationship between braille and data representation in computers?

8. Remind students that a bit is the smallest unit of data in computing.  It can hold either a 1 or a 0.  This is also how we measure data storage in our computing systems. 

9. Tell students that we are going to investigate the storage capacity of our computers.  With a partner, ask them to determine how much storage is on the school computer that they are using and how much is available.  

   • Windows computer storage 

   • Mac computer storage

   •  You can also do this with cell phones or tablets if students have those.

   • If students do not have access to this information, the teacher will need to demonstrate and discuss. 

10. Discuss:  What does gigabyte mean?  Terabyte?   Just like we need measurement units for measuring liquids (cups, quarts, liters)  or weights (pounds, ounces, kilograms), we need measurements for data storage.

11. Students complete the Storage Scavenger Hunt.  Websites for help:

    • https://www.computerhope.com/issues/chspace.htm

    • https://whatsabyte.com/

    • https://www.lifewire.com/terabytes-gigabytes-amp-petabytes-how-big-are-they-4125169

Resources

• 7.3.1: How Computers Work:  Binary & Data video (student resource)

• 7.3.1: Relationship between Braille and data representation (student resource)

• 7.3.1: Storage Scavenger Hunt (student resource)