Book 0 · Lesson 0.1
What is a computer, really?
- Explain how text becomes bits in memory
- Encode a character using ASCII
Computers store everything as binary — voltage on or off, represented as 1 and 0.
From letters to bits
When you type A, the keyboard sends a signal the CPU interprets as decimal 65 (ASCII). That number becomes 8 bits:
01000001Each bit is one switch. Eight switches give you 256 possible values (0–255), enough for the basic Latin alphabet, digits, and punctuation.
Why this matters for Team Radar
Every webhook payload — GitHub PR, Jira ticket, Slack pulse — arrives as bytes on the wire. The ingestion service parses JSON, but underneath it’s all bits flowing through Kafka partitions.
ASCII 65 → binary
Lab: encode your name
Pick the first letter of your name. Use the widget above to see its bit pattern. Write down the decimal ASCII value and binary string in your journal.
Teach-back prompt
Explain to a colleague: “What happens when I press a key?” in three sentences or fewer.