Chapter 01 · What the grid is · 5 min
What a spreadsheet really is
Most people meet Excel as a place to make something look right: a quote, an invoice, a budget you print. That instinct is what makes analysis in a spreadsheet go wrong, because an analyst's sheet is not a document at all. It is a small database with a calculator attached.
This whole track is about that difference. This chapter sets up the vocabulary — cell, range, reference — and the one distinction everything else rests on: the part of the grid you type, and the part you derive.
The grid
Five delivery orders in A1:C6 — one row per order, with a city and an amount in ringgit. Off to the right in column E sits a report block: a label, and a total somebody typed in by hand.
A cell, a reference, a range
Three words, and you have the whole language.
A cell is one box, named by its column letter and row number: C2. It holds exactly one value — a number, some text, a date — never two.
A reference is a formula pointing at a cell instead of repeating what is in it. =C2 does not copy 38.5 into the new cell; it says whatever C2 holds, show that. Change C2 and the formula changes with it. That live link is the entire reason a spreadsheet is worth using.
A range is a rectangle of cells named by its corners: C2:C6 is the five amounts, A1:C6 is the whole table including its header row.
C2 holds the first order's amount. What does this formula show?
Scroll to see all 5 columns →
| A | B | C | D | E | |
|---|---|---|---|---|---|
| 1 | order_id | city | amount_myr | Total (typed) | |
| 2 | 1001 | Kuala Lumpur | 38.50 | 173.65 | |
| 3 | 1002 | Penang | 22.00 | ||
| 4 | 1003 | Kuala Lumpur | 51.25 | =C2 | |
| 5 | 1004 | Johor Bahru | 17.90 | ||
| 6 | 1005 | Penang | 44.00 |
One formula over many cells
SUM takes a range and adds up every number in it. One formula, five cells — and critically, it stays correct if any of those five amounts changes, because it is pointing at them rather than remembering them.
This is the shape almost every formula in this track has: name a range, ask a question about it.
Total of every amount
In E5, add up every amount in the table with a single formula.
Scroll to see all 5 columns →
| A | B | C | D | E | |
|---|---|---|---|---|---|
| 1 | order_id | city | amount_myr | Total (typed) | |
| 2 | 1001 | Kuala Lumpur | 38.50 | 173.65 | |
| 3 | 1002 | Penang | 22.00 | ||
| 4 | 1003 | Kuala Lumpur | 51.25 | ||
| 5 | 1004 | Johor Bahru | 17.90 | ||
| 6 | 1005 | Penang | 44.00 |
The typed number and the derived number
Now look at E2. It says 173.65, and it is correct. It is also typed — somebody worked the total out once and keyed it in. Compare it against a derived total and the difference is zero.
Today.
Add a sixth order to row 7 and the derived total moves; the typed one does not. Nothing turns red. No error appears. The sheet simply starts reporting a number that was true last week — and it looks exactly as confident as it did when it was right.
This is the distinction to carry through everything else: a data block is typed, and it is the only thing you are allowed to type. A report block is derived, and every cell in it should be a formula pointing back at the data. The moment you type a value into the report, you have quietly turned your analysis into a document again.
The typed total and the real total agree right now. What is the difference between them?
Scroll to see all 5 columns →
| A | B | C | D | E | |
|---|---|---|---|---|---|
| 1 | order_id | city | amount_myr | Total (typed) | |
| 2 | 1001 | Kuala Lumpur | 38.50 | 173.65 | |
| 3 | 1002 | Penang | 22.00 | ||
| 4 | 1003 | Kuala Lumpur | 51.25 | ||
| 5 | 1004 | Johor Bahru | 17.90 | ||
| 6 | 1005 | Penang | 44.00 | =E2-SUM(C2:C6) |
So what is the grid, then
A spreadsheet is a grid of values with formulas layered on top. It has no idea what any of it means — that a column is money, that a row is one order, that E2 was supposed to be a total. Excel will not refuse anything you do to it. Every guardrail on this grid is one you put there on purpose.
That is not a complaint about the tool. It is the job description. The next chapter starts with the first thing it will happily let you get wrong: a column of numbers where some of them are not numbers at all.
If you want the formula side in parallel, the free Excel tutorial starts from your very first = and runs to cross-tabs. This track is the companion to it, not a prerequisite — read them in either order.