Methods of capturing, selecting, managing and exchanging data.

— CAPTURING DATA:

capturing data is getting data into a computer:

🧠 Examples

  • Typing on a keyboard

  • Scanning a barcode

  • Sensors (temperature, motion)

  • Microphones (sound input)

methods of capturing data:

  1. manual input:

  • user types data

✔ Advantage:

flexible

❌ Disadvantage:

slow, human error

  1. automatic input:

Barcode readers

  • Scan product codes

RFID

  • Uses radio signals to read tags

Sensors

  • Measure real-world data

✔ Advantages:

  • Fast

  • Accurate

❌ Disadvantages:

  • Expensive

  • Needs setup

🟩 PART 3 — SELECTING DATA

💡 What does “selecting data” mean?

👉 Choosing specific data from a larger set

🧠 Example

Database of students:

Name

Age

Grade

👉 You select:

  • Only students with Grade A

  • Only students aged 16

🔧 Methods

  • Queries (e.g. SQL)

  • Filters

  • Search conditions

⚖ Advantages

  • Reduces unnecessary data

  • Faster processing

❌ Disadvantages

  • Incorrect selection → wrong results

  • Requires correct queries

🟨 PART 4 — MANAGING DATA

💡 What is managing data?

👉 Storing, organising, and maintaining data

🧠 Includes:

  • Databases

  • File systems

  • Updating records

  • Deleting data

🔧 Key methods

1⃣ Validation

👉 Checks data is sensible

Example:

  • Age cannot be -5

2⃣ Verification

👉 Checks data was entered correctly

Example:

  • Enter password twice

3⃣ Data structures

👉 Organising data efficiently (tables, records)

⚖ Advantages

  • Improves data quality

  • Reduces errors

  • Makes data easier to use

❌ Disadvantages

  • Takes time and resources

  • Can slow systems

🟥 PART 5 — EXCHANGING DATA

💡 What is exchanging data?

👉 Sending data between systems

🧠 Examples

  • Sending emails

  • Uploading files

  • APIs between systems

🔧 Methods

1⃣ File transfer

  • Sending files between devices

2⃣ APIs

  • Systems communicate directly

3⃣ Protocols

Rules for communication:

  • HTTP

  • FTP

⚖ Advantages

  • Enables communication

  • Allows systems to work together

❌ Disadvantages

  • Security risks (data interception)

  • Compatibility issues

  • Data corruption during transfer

🔐 VERY IMPORTANT (OCR LINK)

👉 When exchanging data:

  • Encryption is often used

  • Hashing may be used to check integrity