Im curious. What types of executable formats are there?? Ive seen PE4.0 something and .coms and others. What are the diffrence between them?? Can someone give me a link to any site that would be helpful??

Well, links:
ELF File format
PE File format

Basically, there are a lot of executable file formats, usually a certain file type is associated with a certain OS.

ELF - *Nix
a.out - *Nix/BSD (BSD counts as a *nix?)
mscoff - Windows (Older format)
PE - Windows (Newer format)
com/binary/flat - can be used by DOS or in real-mode.

That all i can remember off the top of my head. im sure you can find way more on each of the formats (and probably a good list too) on google somewhere.

memory image (.COM) - raw file loaded within one 16bit segemnt at offset 100h

SYS - dos driver (like .COM but starts with small table of pointers)

MZ - DOS executable / driver. contains header, always starts with "MZ" or "ZM" bytes. Can be used as driver and normal executable both (eg. same file can be working DOS driver and executable).

PE - Win32 executable. they always contain MZ executable too, and "PE" part starts at the end of "MZ" part (which usually contains only writing "Sorry, this is win32 routine" for case someone runs it under DOS).

LE - Linear executable - adopted for VxD drivers for old win32s drivers some other operating systems. don't know much about it. not supported by fasm.

WDM driver - newer win32 drivers, it's kind of PE, don't know much about it.

OBJ - linkable file (it has to be linked to become executable). I think there are many types of them.

DLL - dynamic link library - type of PE, win32 library that can be linked at run-time. I think PE executable can work as DLL as well (one file is both excutable and library)

COFF - common object file format - like .OBJ but little more standardized. Needs to be linked to make executable.

ELF - executable linkable format - you see it from description, used in linux (and unix?)

note: dos/win32 doesn't differentiate runnable files by extension. it's only that command.com alows you to run only files that have .COM or .EXE extenstion (you can run many more in win32 - SCR, CPL, ...) and resolves it's type depending on contents of file (for example win32.com is really a MZ file etc.)

http://www.wotsit.org - i hate sites that require "www"

? Even truncated "wotsit.org" works for me...

maybe your browser automatically adds "www." if URL doesn't work. Or maybe i really should upgrade from 2003's opera. But i still hate admins who can't fix this.

download FireFox

My browser probably adds it, but not explicitly (I still see only "wotsit.org").
I use Firefox/1.0.7.

i just liked old opera - compact and small. i don't need tons of features, i don't want to learn new interface, i don't want to setup e-mail & news clients AGAIN (if mozilla has ones) etc. i would rather spend time writing fasmlib

Im using opera too. Alternate with IE. my ram cant take firefox. its a resource hog. But sure its better than IE. Opera has too man bugs. its now version 10 and still a lot. It crashes a lot for me.

They should make opera open source. Its now free anyways.