ES6 vs Vanilla (Vanilla Replacement for ES6 code) For object merging ES6 let obj1 = {a:1}; let obj2 = {b:2}; let mergeTwoObjs = {...obj1,...obj2} ; // {a:1,b:2} Vanilla var obj1 = {a:1}; var obj2 = {b:2}; var mergeTwoObjs = Object.assign({},obj1,obj2); // {a:1,b:2}