as a 63 year old i know nothing about programming.i want to purchase an arduino but which one? i see uno r3, mega , mega with android?????? now leonardo. to get the best possible experiance out of my arduino plus value for money,so i dont want to buy cheap then want another shortly.any help is welcome.......mally
The UNO would be perfect to start out with, and there are plenty of examples that come with the software.
I would also say a Uno is good, but also remember to have some fun with programming it might be good to buy one shield (PCB you plug on top of the arduino) that can do some stuff you like, like some LED's, a little motor, some sensors etc.
An arduino on its own wil get a bit boring. .
I would advise you to look for a C language primer. Without some knowledge of the language you will be limited to making small adjustments to already available examples, and you won't be able to communicate effectively with the forum. As for the board the Uno is your best choice; it's called a reference version, meaning it will be supported (by people and by software) for a reasonable period. But an Arduino by itself can do no more than blinking a led and write messages to a terminal window, so you'll probably want to get wires, leds, buttons, sensors, a breadboard. If you don't have them already you may want to look for a starter kit.
No matter which one you get, you'll soon find yourself wanting another one.
I started with Uno. Now another one is in the mail, countless tinys are scattered on my desk and I just can't get enough.
Shpaget:
I started with Uno. Now another one is in the mail, countless tinys are scattered on my desk and I just can't get enough.
Is there a 12 step programme to help with this addiction? 
I'm not aware of it, but after posting my post above I realized that I'll soon be finishing a project I've been working on for the past two weeks and that to implement it I'll need a bunch of Arduino compatible chips...
I'm already scouting both local and international web shop for atmega328s. I'm looking for those that offer discounts on 10+ orders.
It's not addiction if you can stop at any time. 
On topic, I would also like to emphasize spatula's advice.
I also feel that my limited programing skills are quite limiting when it comes to even reading other peoples code. I manage to use ready made libraries and implement them in my rudimentary programs, but I fear that I'm not at the required level to truly be capable of even approaching the potentials of an Arduino.
That's why a c++ book is in the mail as well (I picked Programming: Principles and Practice Using C++ by Bjarne Stroustrup).
Is there a 12 step programme to help with this addiction?
Can I interest you in my new AVR patches?
mally:
as a 63 year old i know nothing about programming.i want to purchase an arduino but which one? i see uno r3, mega , mega with android?????? now leonardo. to get the best possible experiance out of my arduino plus value for money,so i dont want to buy cheap then want another shortly.any help is welcome.......mally
The below mega and ethernet shield would make for a good start before getting more parts. The ethernet shield also has a uSD card slot.
Look for a starter kit such as this onehttp://www.oomlout.co.uk/starter-kit-for-arduino-ardx-p-183.html. It's not which Arduino you by that matters so much as the bits to go with it!.
As a beginner avoid the Due as it use 3.3v and not 5v this will avoid you having to use level converts to interface with the most common bits of external hardware.
Mark
That's why a c++ book is in the mail as well (I picked Programming: Principles and Practice Using C++ by Bjarne Stroustrup).
is a great book BUT it is overkill for the Aduino as you can't really use 90% of what he talks about and he assumes your already a good to excellent programmer.
Looking for something with a title like "An introduction to programming with C/C++" is a better bet. I'll have a look around and see what I can find.
Mark
Kelley and Pohl's "A Book on C" is much more readable than Stroustrup, IMO, and whilst most examples are C and not C++, it is a lot easier to follow.
Well, if you have suggestion, I'm always open to them.
And even if Stroustrup sits on a shelf for a while, I'll still get to it someday 
I gave up on ever trying to understand my first edition Stroustrup about twenty years ago.
And even if Stroustrup sits on a shelf for a while, I'll still get to it someday
I gave up on ever trying to understand my first edition Stroustrup about twenty years ago
I'am about the same.
Mark
This is the first ever book on C, Amazon.co.uk : 0131101633 and as second hand copies are cheap well worth a look.
This article is not bad What is C? - The Basics of C Programming | HowStuffWorks.
Mark
AWOL, hopefully he revised his writing style in the last 20 years.
Holmes, you think a 35 year old book is still up to date? Well, I'm sure it is for basics, but in general, I would assume there has been some change in the approach to programming.
I got "C++ ALL-IN-ONE For Dummies" for $39.95, but haven't had time to read it. 834 pages with CD. Got to be a lot of stuff in there.
I'm a noob to, or rather a retread. I found "Getting Started with Arduino by Massimo Banzi was a good start, then Programming Arduino by Simon Monk, then Arduino Cookbook by Michael Margolis. I'm also playing with xBees, and found Hands On Xbee by Jonathan Titus to be good. Got them all as eBooks on Kindle, so using the Kindle App on my mac provides useable inks--no typing!!
Oh, and I'm 66. I dove back into electronics and programming because I bought a quadcopter www.multiwiicopter.com and wanted to understand it better. Now I'm working on an autopilot/rc steering for my open ocean stand up paddle board.
Holmes, you think a 35 year old book is still up to date? Well, I'm sure it is for basics, but in general, I would assume there has been some change in the approach to programming.
Non of the basics, int's, bytes, floats, for, do, while, if, all the operators, functions, includes, ect have change and K&R does not assume a great deal of programming experience. K&R does not teach programming it teaches C and its use.
There have been some change in the approach to programming but that's to add things like classes ,OOD/OOP.
Mark