React is very hot stuff right now, most aspiring web developers will probably end up looking at it. Sometimes being to eager to jump head first into a library like React means you end up having this problem:
I know React but I don’t know Javascript
Well why is this a problem? Not understanding the lower level of libraries like React means you are not going to be a versatile, the lower level here being Javascript and the browser. Many paradigms of Javascript are abstracted away when using React, but there are always going to be times when you need to be able to rely on your Javascript understanding to disover a solution, rather than your React understanding. If you are a React dev who feels like they are blagging it in this regard – stop and take a deep dive into the language of Javascript, you will slow down now to go faster forever.