What is the difference between a Deferred and a Promise?

Callback vs Promise? Which one is faster? How do you use Promises? What is the difference between async and sync code? What is "this"? React class components and binding "this". What is closure? How can you stop a loop? Strict Mode, Flexbox, CSS specificity. 0. Hackerrank (Front End): DOM manipulation with vanilla JavaScript. You need to render a list of items in the right place based on their status. There are three tabs and statuses: Active, In Process, Completed. 1. Hackerrank (Software Engineer): Maximum Occuring Character (hashmap), Simple version of balanced string (hashmap or stack), Consecutive Sum (you need to find the starting index at which a sequence of consecutive numbers whose sum is equal to the target value) Sliding window solves this problem with O(n) 2. Live Coding (Front End): Make a counter with all React/Angular fundamentals (state management, passing props, etc) 3. Live Coding (Front End): Render a list as a table, sort data, implement routes based on list parameters ( a little bit complicated but just look at routing stuff in React)