diff --git a/index.md b/index.md
index 2a23dcf..5bbff8d 100644
--- a/index.md
+++ b/index.md
@@ -9,7 +9,22 @@ Welcome to the website for David Calc.
 
 ### Features planned
 * Divide by zero protection
-* Binary conversion
-* x86 Docker version
-* GUI with [Raylib](https://raylib.com)
-* Linux and Docker code in the GitHub repo
+* GUI with Visual C++
+
+### File explanation:
+main.cpp: Version for running from the desktop
+terminal.cpp: Version for running from the Command Prompt / Terminal (naming depends on OS)
+Dockerfile: File to build the docker image.
+
+### How to build
+
+#### Regular
+First, ask this question. Are you going to double-click this in the file manager / on the desktop or type `calc` in the command line to run it? If you are gonna use the command line, use terminal.cpp. If you are going to use your file manager / the desktop, use main.cpp.
+
+Windows:
+`g++ <main.cpp / terminal.cpp> -o calc.exe`
+To run it, type `calc` at the prompt, or double-click the executable.
+
+Linux / macOS:
+`g++ <main.cpp / terminal.cpp> -o calc`
+To run it, type `./calc` at the prompt, or double-click the executable.