- data types
- type casting (implicit, explicit)
- closure / scope / hoisting
- operators (arithmetic, comparison, logical, type, string)
- events (dispatching, handling, preventing)
- ES 6 / 7 and so on
- inheritance
- FP (concept, methods)
- functions (type, calling context, arguments, generators)
- callbacks vs promises
- error handling
- DOM (API, selectors, operations) / observers (mutation, resize, intersection)
- Web Storage API
- AJAX (XMLHttpRequest, fetch)
- service / web workers
- graphics
- patterns (design, MV*, modular)
- libraries / frameworks (best practices)*