Installing a mod for Soldier of Fortune 2 is a simple process. In most cases, all you need to do is copy the client-side mods files to your Soldier of Fortune 2 root directory (where SoF2 is installed).
Step 1 - Download and Extract Mod
Download the client-side version of the mod you want to play on and extract the files to your PC.
Step 2 - Copy and paste the mod directory
Copy the extracted mod directory and paste it into your Soldier of Fortune 2 root directory.
For RoCMod, for example, you would have to copy the directory named "rocmod" and paste it into the directory in which your Soldier of Fortune 2 is installed.
What is a mod?
Mods (short for modifications) as a term are a bit ambiguous as they cover a variety of meanings. Any change in the standard appearance or the standard functionality of SoF2 can be classified as a "Mod".
When people talk about "mods" they are usually referring to what modified version of the game a server is running. Shortly after Soldier of Fortune 2 was released, Raven also released its Software Development Kit (SDK) to the community.
The release of the SDK allowed anyone familiar with coding in C to make any changes to the game to create their own unique version of SoF2MP. Soon after the SoF2SDK was released, a number of server administration and client-side mods popped up, some good, some bad, and some just plain crazy. Some of the most popular creations like RPM, GoldRush, OSP, and RoCmod are still in use today!