A. What Is Data?
๐ฏ Learning Goals
By the end of this lesson, you'll be able to:
- โ You can explain what data and information are
- โ You can find data in everyday life
- โ You can tell the different types of data apart
What Is Data?
A Simple Definition
Data is facts or values recorded as numbers, text, symbols, or other forms through observation, measurement, or a survey.
๐ก What Is Information?
Information is the meaning produced by organizing and interpreting data so that it can answer a question or help us make a decision.
For example, "45 votes for chicken, 30 for pizza, and 25 for tteokbokki" is data. Comparing those values tells us that "chicken is the most popular": that is information.
In short, data is recorded facts or values, while information is the meaning we learn from data.
๐ Analogy: School Life
Think about the data you run into at school:
- ๐ Test scores: 85, 92, 78
- ๐ Attendance sheet: present, absent, late
- ๐ PE records: 50m dash 8.2 seconds
- ๐ Library checkouts: book title, checkout date, return date
All of these are data!
Why Does Data Matter?
Example: School Lunch Menu Preferences
Collect data: ask 100 students
| Menu | Votes |
|---|---|
| Chicken | 45 |
| Pizza | 30 |
| Tteokbokki | 25 |
Conclusion: Chicken is the most popular! โ Let's put chicken on the menu more often!
Data in Everyday Life
Data Around Us
Let's find the data you run into over the course of a day.
| Time | Situation | data |
|---|---|---|
| Morning | Checking the weather app | Temperature 15ยฐC, humidity 60% |
| Lunch | School lunch nutrition info | 650 kcal |
| Afternoon | Playing a game | Score 1,250, level 12 |
| Evening | Watching YouTube | 1 million views, 50,000 likes |
๐ก Aha Moment
Every day, we tons of datalook at and use!
Types of Data
1. Number Data (Number)
# Data expressed as numbers
temperature = 25 # Temperature
score = 92 # Score
height = 165.5 # Height
students_count = 30 # Number of students
Features: You can do calculations! (average, sum, comparison)
2. Text Data (Text)
# Data expressed as text
name = "Kim Cheolsu" # Name
city = "Seoul" # City
weather = "Sunny" # Weather
grade = "A" # Grade
Features: Used for sorting or distinguishing things!
3. True/False Data (Boolean)
# Data you can answer with yes/no
is_student = True # Are you a student? Yes!
has_pet = False # Do you have a pet? No
passed = True # Did you pass? Yes!
Features: Used for evaluating conditions!
Organizing Data
Organizing with a Table
When you organize lots of data into a table, it's easy to read!
| Name | Korean | Math | English |
|---|---|---|---|
| Kim Cheol-su | 85 | 92 | 78 |
| Lee Young-hee | 90 | 88 | 95 |
| Park Min-su | 78 | 95 | 82 |
๐ What if you show it as a graph?
Number data, a graphwhen shown as a graph, can be compared at a glance!
In this course, you'll learn about data and visualization!
๐ฏ Quiz
Show Answer
Answer: C) The thought "I should study hard"
Data is a record of observed or measured facts and values.
- โ 85 โ recorded as a number
- โ "Sunny" โ recorded as text
- โ A thought โ something that isn't recorded is not data!
is_raining = Truewhat type of data is it?
Show Answer
Answer: B) True/False data
Trueand Falseis Boolean (True/False) data.
๐งฉ Key Takeaways
What you learned in this lesson:
| Concept | Description |
|---|---|
| Data | Recorded facts or values gathered through observation, measurement, or a survey |
| Information | Meaning learned by organizing and interpreting data |
| Number data | Can be calculated (scores, temperature) |
| Text data | For categorizing (names, weather) |
| True/False data | For evaluating conditions (True/False) |
Preview of the Next Lesson
In the next lesson, we'll learn where you can get data !