As the drum of time beats forward, we gradually learn new skills.
What about the skills that go to the sideline?
MS Access. Used this heavily in 1998 working for Florida Power. We had a Visual Basic that reference the Access database through COM, to give the user a seamless view of switching between the two apps. Was kind of cool, they really pushed the limits of Access back then.
And speaking of COM components, and distributed DLLs, I don't program those anymore.
And how about Java J2EE, the 1990's version. Now they have newer versions, Spring, Hybernate, even Struts is passe.
How about classic Visual Basic, the Object Oriented want to be language. And for that matter, I used to program in classic ASP, talk about spaghetti code, which reminds me of PHP which I dabbled in at the School Board.
In the 1990's I did mostly Oracle programming, PL/SQL, tnsnames, Toad, SQL editor, haven't done much of that lately.
As you can see, much of what we learn goes away. Thing is, I can sit down today and code like there was no time in between. I haven't forgotten the languages, just out of practice.
So name a few languages you're using today, and think if you'll be doing them in 2 years.
Makes you wonder how deep you need to learn each language, or do you learn the basics and use Google for the difficult stuff.
And so it goes~!