buffer

const buf1 = Buffer.alloc(10);
const buf2 = Buffer.alloc(10,255);
const buf3 = Buffer.allocUnsafe(10)
const buf4 = Buffer.from([1, 2, 3]);
const buf5 = Buffer.from('tast');//默认utf-8
console.log(buf1,buf2,buf3,buf4,buf5)