Yeah, It will work on both, so I'm gonna teach you how to make it on both.
People always say to go to "Run" and type in %appdata%, then go to .minecraft/techniclauncher, and then put your texture pack into there, but you can also just open minecraft, then click texture packs, then hit the "open texture pack folder" button, and then you'll be right there. If you wanna make a texture pack from scratch, you're gonna have to go into the bin folder and go to minecraft.jar. That's where all the files are. Once you've got the files, you put it in a .zip folder and then you should be able to run it. I might make a thread of just the default textures of everything in tekkit so people who want to make a texture pack can just download it and then edit it.
When you do get the files, you wanna make sure that you keep them in every folder that they were in in the minecraft.jar folder.