cannot execute binary file

I had this really weird issue on Ubuntu:
* An executable works fine on my laptop.
* Then I scp it to the server.
* On the server I get the following error messsage: "cannot execute binary file"
* So after some googling I found:

You are probably trying to run a 64-bit [executable] on a 32-bit Linux system...

http://www.kods.net/transferred-to-install-oracle-9i-in-linux-the-whole-document/

Go figure. I've been so spoiled with java and python, that I forget there are still things you need to compile for the platform you want to run it on...