querySelector vs getElementById

Get Element By Id

• It returns a node list which is live, meaning if you add or remove any element from the DOM the node list will update
• It is faster relative to the query selector methods

Query Selector

• It returns a node list which was available at the time of the execution

Also Read:

1. Getting started with es6 iterators and iterables
2. Default function parameters
3. Testing promise sequence using mocha, chai, chai-as-promised, sinon
4. imperative vs declarative/functional programming
5. Promise javascript examples