Lesson 6 of 8
The big picture
Show on a big screenHere are the five ideas, smallest first.
| Idea | Remember |
|---|---|
| One switch | A bit can be pictured as one switch with two states. Both ends must agree what each state means. |
| More switches | Each new switch doubles the patterns. Five switches give 32. |
| A code | A code is an agreed table. A pattern with no line carries nothing. |
| Rows and columns | A row is a record. A column is a field. One field holds one kind of fact. |
| Sort and filter | Sorting orders whole rows. Filtering hides rows. Neither changes a fact. |
One switch carries almost nothing. Eight make a byte, and a byte can hold a letter. Enough letters make a word. Enough words make a row. Enough rows make a table you can sort and filter.
Your school handbook says a record has attributes. Attributes are the kinds of fact a record holds. It says structured data is kept in rows and columns. A column of one kind of fact is a field.