The Rorke Files are the collectible in Call of Duty: Ghosts, similar to the Intel in previous games. There are a total of 18 files located across all of the campaign missions and they take the form of a laptop. When you get close to one, hold Square (PS3) or X (Xbox 360) to upload the file and collect it.
Each mission has one of these files and once you get it, the game saves it automatically, even if you die directly after it. You do not have to reach the next checkpoint and can immediately quit to the main menu. Obtaining all Rorke Files will get you the Audiophile trophy/achievement.
#1) Ghost Stories - This file is located inside of a house when you appear back on Earth. After the sequence where an earthquake starts happening, run up the street and you'll see a car you can jump over. Go inside the house right after and you'll find the file on the floor straight ahead.
#2) Brave New World - You'll find this file in an allied camp you arrive at after using a MAAWS rocket launcher to shoot down an attack helicopter. Head inside and up to the third floor, to find it on a table.
#3) No Man's Land - Not far into the mission, you will do battle with some enemies near a broken windmill. Go past this and you'll have to pass through a building, where you'll find the file inside.
#4) Struck Down - This file is inside of the room you breach. Kill all of the enemies first, then look in the lockers to the left of where you entered the room to find it.
#5) Homecoming - This file is located near the beginning of the mission, where you are in an allied camp. There will be a small house you will have to pass through, with the stairs continuing the mission. Instead of using the stairs, go to the left of them and find the file sitting on a makeshift table.
#6) Legends Never Die - You'll find this file after the section where you end up in the waters. Kill the two enemies with your knife, then follow the mission until you cross a crumbling platform and into a building with two more enemies. The file is right behind those two enemies.
#7) Federation Day - This file is located after you rappel down a building. Once inside, go to the left and enter the room around the corner. It's on a desk on the right side of this room.
#8) Birds of Prey - This file is right on the desk when you encounter Rorke himself. Make sure you grab it before the mission ends.
#9) The Hunted - You'll have to regroup with some of your teammates near the beginning of the mission. Once you find them, you'll see a waterfall to the left of them. This file is located on the ground to the left of the waterfall.
#10) Clockwork - You can find this file after you have to activate your Nightvision Goggles when the lights go out. Go through the metal detector and into an office area straight ahead. There's only one office here that you can enter, so go inside and find the file sitting on a desk.
#11) Atlas Falls - This file is located after you end up in a control room where you ally takes out the single enemy inside. Before activating the console, look to the right to find the file on top of a file cabinet in the little side room.
#12) Into the Deep - You'll find this file after using a torpedo to blow up the warship. Follow your ally through a rusty tanker to find some enemies. The file will be on a rock on the ocean floor on the right, but it doesn't appear right away. Kill the enemies first and it should appear on the rock (it drops down from above).
#13) End of the Line - When you enter a very, very large room with some rockets and a huge satellite, go down the stairs to your left and turn around at the bottom to find the file.
#14) Sin City - This is located in the casino area, past the point where you allies hold up a gate for you. As soon as you crouch under the gate, you'll find the file to the left on a table.
#15) All or Nothing - Turn around at the beginning of the mission and look in the bunks on the left side with the lights on. It's on the bottom bunk.
#16) Severed Ties - After launching the mission, go through the door at the bottom of the stairs that you have to wait for your ally to open. Take the first right and enter the small room on the left to find the file sitting on one of the computers.
#17) Loki - After the explosion that launches you into space, kill the two enemies that show up. Once you do, look to the left of the orange debris on your left to find this file floating in space.
#18) The Ghost Killer - The last file is located in the same room where you begin. It's in the corner of the room behind you.