Number and BigInt Boundaries
Most everyday calculations use Number. Number("42.5") converts numeric text into a number. BigInt represents whole integers beyond the range where ordinary Number values can safely distinguish every integer.
javascript
const parsedScore = Number("42.5");
const invalidScore = Number("north");
const largeTicket = 9007199254740993n;
console.log(parsedScore);
console.log(Number.isNaN(invalidScore));
console.log(largeTicket > 9007199254740992n);
Checkpoint
Number("north") is not a usable number, so Number.isNaN() reports true. BigInt literals end with n; do not mix a BigInt and a Number in arithmetic without an explicit conversion.
Learn more
MDN's references for Number and BigInt cover conversion, safe integer limits, and BigInt operations.