Learning New Skills and Keeping Up to Date: Advice on Memory Retention

Question

I'm having a difficult time retaining the programming skills I'm actively trying to learn in an effort to apply for a junior developer position.

What I'm finding is that I can easily master isolated topics (for example, details about how Java's Container classes work and the different ways to sort a given container), but I find that when I move on to new topics I forget maybe 80% of what I learned (a few months down the road).

Sure, with good notes, I can get back up to speed much more quickly, but my question to those of you who are already in the professional field - is this common (this constant need to re-learn things you once felt you'd never forget)? If so, how do you get around it? Should I accept that I'll probably only be an expert in the narrow domain that I currently use on a day to day basis?

Thanks for the feedback.

Answer 1

My father always said:

You don't need to know everything, you only need to know where to look it up

(roughly translated).

Going with your example, if you find you need to sort a collection very often you will remember after you've done it a few times, if you don't do it for a long time you will forget it again. That's perfectly normal imo.

So what I'm trying to say is there is no point in knowing stuff off the top of your head if you don't use it anyway as long as you know where you can look it up if you need it again. I hope that made sense.