. variables
. code
. conditional code (if statements)
. repeating code (loops/while/until/for)
. code grouping (procedures/methods/functions)
. variable grouping (records/structs)
. boolean logic (extension to conditionals)
. Object oriented coding (think: code+struct grouping)
. namespaces (think: grouping of objects)
. generics / reflections
. pointers
(certain languages expose this completely
(some implicitly: through pass by val or pass by ref
(some implicitly: by primitives vs objects
. preprocessor (only certain languages)
. recursion (repeating code but through function)
. functional features
How do you pick these concepts up? Few ways, but I think the following three are most common:
1) Old School Method :: Understand what is happening on the bare metal, and then work building syntactic sugar between what is happening really, and what you want to happen.
Assembly
-> C
-> OPP (C++/Java/C#)
-> scripting (Perl/Python/Ruby)
-> Functional (Lisp)
Scripting (Python/Ruby)
-> C#/Java/C++
----
Libraries are in itself own big concept. Languages without libraries are bare, and, outside of curiosity, not practical. Very often knowing a language implies not only understanding of language grammar, but also it's libraries
You can think that libraries define half of what is considered programming language. For C++ you got STL/Boost. For Perl you got CPAN.
Kind regards
Adam Żochowski
It's like asking how to climb Mount Everest. The flippant answer of course is 'by taking the first step'.
What you learn first is different for everybody, just like that first step on to the path that leads to the summit of Mount Everest is different for everybody. It depends, in the first place, on where you currently are.
So without knowing where you currently are it is next to impossible to answer the question in a way that would make sense to you.
Could you maybe describe a bit of what you already know, your skills and your experience to date? That would help enormously.
I think the field is too new, changing too rapidly, and has too many people with widely varying goals (computer science vs make a small web site in PHP) to really have much that's 'universal' besides "get out there and practice!".
Tasks that save you time and effort are a good place to start. Tasks that entertain you are another.
In this regard, a scripting language with a good interface to your system (file access, graphics/presentation support, network support) is often cited as a good place to start. Many people suggest Python.
As you move to tackling larger problems, and/or growing your previous work, you'll find it beneficial to learn more about designs and techniques that aid in staying organized, keeping your work maintainable and efficient, etc. At that point, you'll want to look beyond the references for the language you started in and learn more general principles. (But even when you start, look for the BEST references in the language of your choice. The best references incorporate some of this context and explain it well, giving you a head start and helping you to avoid "bad" practices you may latter have to "unlearn".)
P.S. Perhaps implied in the above, the environment you want to work in / control will influence your choice. For "general" programming -- freestanding programs running on your machine -- you might find e.g Python the best starting point. If you mostly want to control things in your browser, then Javascript (along with HTML, CSS, and the DOM model -- which is already incorporating a quantity of semi-arbitrary detail that frustrates some people). If you were trying to ease administering a UNIX-flavor environment, you might consider Perl. If you spend most of your time in Microsoft Office documents, then Visual Basic for Applications (VBA) or whatever it is these days.
How long it takes depends largely on you. Some people, particularly with a strong motivation to accomplish specific things, learn quite a lot in a couple of months. On the other hand, I've worked with people having technology degrees who nonetheless seem fairly clueless.