0 one of a set of numbers that is put on things produced in large quantities, such as computers, televisions, paper money, etc. so that each has a different number and can be recognized --
1 a number on a product, esp. electronic or electrical goods, that is different from all the other product numbers, used to prove who it belongs to if it is stolen or damaged --
2 one of a set of numbers that is printed on paper money, on some products, etc. so that each has a different number and can be recognized: --
Several machines carried the same serial numbers from the manufacturer.
We can complete it step by step however long the road is and it can't be completed however short the road is if you don't even mark your footprint.
Можем да го завършим стъпка по стъпка, колкото и дълъг да е пътят и не може да бъде завършен, колкото и кратък да е пътят, ако дори не маркирате отпечатъка си.