diff --git a/README.md b/README.md
index 9b8e6c8663c5074e1c559eb012d73cda5ab2afa6..9c6c8ae351f109b1f8df62487b6966332959eead 100644
--- a/README.md
+++ b/README.md
@@ -2,6 +2,13 @@
 
 CHIP-8 emulator written in rust 🦀.
 
+## Goals
+
+* Performance 🏎
+* Separation of concerns - presentation vs logic
+* Simplicity
+* Compatibility
+
 ## Inspiration
 
 * [Guide to making a CHIP-8 emulator](https://tobiasvl.github.io/blog/write-a-chip-8-emulator)
diff --git a/src/chip8_neo.rs b/src/chip8_neo.rs
index 3698867260ccfdfd2a37c38ff88aea3589b6d467..3d505894082bc13080370359590d8851ba011748 100644
--- a/src/chip8_neo.rs
+++ b/src/chip8_neo.rs
@@ -1,3 +1,8 @@
+pub const DISPLAY_WIDTH: usize = 64;
+pub const DISPLAY_HEIGHT: usize = 32;
+pub const RAM_SIZE: usize = 4096;
+
 pub struct Chip8Neo {
-    vram: [u8],
+    ram: [u8; RAM_SIZE],
+    vram: [u8; DISPLAY_WIDTH * DISPLAY_HEIGHT],
 }