what do these phrases mean
 

whenever i download a distro a set of these phrases come up that are supposed to describe the characteristic of my computer that i plan to install the distro on but i don't understand what they mean maybe you can make it clearer to me

here are the phrases
[alpha][amd64][arm][armel][hppa][i386][ia64][mips][mipsel][powerpc][sparc][s390][source][multi-arch]

They list various CPU architectures.

The two super common ones are AMD64 and i386.

Those two also overlap. If you have an ordinary (common recent model) 64 bit CPU from Intel or AMD, your CPU can run either software architecture AMD64 or i386. If you have an ordinary older CPU from Intel or AMD it can run i386 but not AMD64.

Intel made some 64 bit CPUs that ran ia64 and not AMD64 nor i386. But the current common Intel models are AMD64 architecture.

Those are different machine architectures. If you don't know what yours is its probably either i386, ia64, or amd64. ia64 and amd64 is for "64 bit machines" and i386 is for pentium 1-4 or most other recent intel/amd processors. If you have a 64 bit machine you can still install i386, you just will only run 32 bit apps. If you want 64 bit edition of linux then choose amd64 or ia64 as far as which one depends on your specific processor.

The other ones are rare for consumer desktop computers the exception being powerpc for old macs, and I believe sun distributes/distributed some sparc.

so the most common machine will be i386 therefore it should be the one to download

i was downloading debian to see what it is like but i saw more than one architecture but my gut told me to pick the i386 (it was right for once) but when i looked at the cd images there for download theres was atleast 30 do i have to download all of them or just one

http://cdimage.debian.org/debian-cd/5.0.3/i386/iso-cd/
http://www.debian.org/CD/http-ftp/#stable

The ia64 is pretty much just for the Itanium processor (very few people have them at home). The amd64 versions are for both amd and intel 64bit "home" computers.

Generically i386 means 32bit and amd64 means 64bit. Which one you choose (on a machine with a 64bit cpu) is dependent on what you are going to be doing on the machine.

If it is a new machine, the only common CPU type is the type that will work with AMD64 and will also work with i386.

If you really don't want to even figure out whether you have a new CPU or an old CPU then you are correct to just download the i386 version.

If you have a cpu that will work with i386 but also will work with AMD64, you might want to figure out which will work better.

If you have a really tiny amount of ram (512MB might be tiny these days, less than 512MB is tiny) or you have a really tiny amount of hard disk, then i386 will work better than AMD64.

If you have a really large amount of ram (16GB is really large, 8GB might be really large) or you run certain kinds of massive computation (maybe re encoding video files) the AMD64 will work better (assuming a CPU new enough for AMD64 to work at all).

For the big majority in between, it is almost impossible to predict which of i386 or AMD64 will work better and whichever of them works better won't work much better.

the usual

openoffice.org
skype
pidgin
frets on fire
movies
music
etc...

Assuming you have a 64bit cpu and you do not intend to do much media conversion, then it is pretty much a coin flip. For the tasks you have listed 32bit may have a slight edge for systems below 512 ram and 64bit will have a slight advantage on systems that have more than 4gb ram, but between those two extremes there is virtually no advantage to either.

anyone knows what "i686" is?, i run pentium 4 and some time ago I checked( i dont remember how ) and saw that my machine is i686, so i guess that the project I'm writing on my machine (Slackpack) is released on i686.

so everytime I release a new version I add an "i686" on the package name
(a Slackware guy should help me abit here, thank you)
although it can run perfectly on 64bit Slackware based computers.

a while ago though, I've noticed somewhere on the internet that pentium 4 -as said above- is "i386" well ok... now I'm confused...

3questions:
-what arch is my machine?!?!?
-what is i686?
-should i start adding "noarch/i386" on every release package I make for my project or stick to "i686"? (honestly I don't see a difference)

thanks and sorry for my poor English...

i386 was the earlier version. All post 386 (of the X86 line) can run 386 code. i686 added to the i386 code. However the revese is not true a 386 cannot run 686 code(it just does not have all the instructions).

If the code you are building uses i686 instructions then you should mark it as i686.

Maybe this will help some:

http://en.wikipedia.org/wiki/X86

hmmm thanx m8, the good thing is that my project releases names doesn't include a wrong arch! (yes im a bit shamed now hehe :P )