Our Story
Why Pebble?
The name isn't arbitrary. Long before apps, spreadsheets, or even paper, people counted with stones. Literally. A handful of small rocks laid out on the ground was humanity's first calculator — and from those pebbles, all of mathematics grew.
Ψῆφος — Psifos
In ancient Greece, the word for a small stone or pebble was ψῆφος (psifos). The same word was used for counting, voting, and reckoning. To calculate something was literally to move pebbles — arranging and rearranging stones on a counting board to add, subtract, and keep track of quantities.
The abacus itself descended from this practice: grooves scratched into sand or stone, with pebbles slid along them to represent numbers. Psifos was at once the tool and the act — the pebble and the thought.
"The Greeks cast their votes with pebbles, and counted their goods the same way. Stone was their language of number."
— On ancient Greek counting practicesCalculus — the Latin pebble
The Romans inherited the idea and gave it a new name. Calculus in Latin simply means small stone or pebble. Roman merchants and tax collectors used calculi — little stones — on counting boards to tally transactions, measure land, and manage the empire's vast accounts.
From calculus came calculate, calculation, and eventually the entire branch of mathematics that Newton and Leibniz would name after it centuries later. Every time you press equals, you are echoing something people have done with stones since before writing existed.
"Calculus: from Latin, a small stone used in reckoning."
— Oxford Latin DictionaryA pebble in your pocket
We named this calculator Pebble as a quiet nod to that long lineage. The tools have changed — from river stones to abacus beads to transistors to a webpage on a phone — but the act is the same. You have a number in mind. You want to know what it becomes. You reckon.
Thousands of years on, the pebble is still doing its job.