var path = require('path');
console.log(path.isAbsolute('../testFiles/secLayer'));//false
console.log(path.isAbsolute('./join.js'));//false
console.log(path.isAbsolute('temp'));//false
console.log(path.isAbsolute('/temp/../..'));//true
console.log(path.isAbsolute('E:/github/nodeAPI/abc/efg'));//true
console.log(path.isAbsolute('///temp123'));//true

path.resolve(from, path.relative(from, to)) == path.resolve(to)

var path = require('path');
console.log(path.relative('C:\\\test', 'C:\\\impl\\bbb'));//..\impl\bbb
console.log(path.relative('C:/test/aaa', 'C:/bbb'));//..\..\bbb
console.log(path.relative('C:/test/aaa', 'D:/bbb'));//D:\bbb