diff --git a/src/Cartridge.cpp b/src/Cartridge.cpp
index 2a33986..7bfe87c 100644
--- a/src/Cartridge.cpp
+++ b/src/Cartridge.cpp
@@ -8,7 +8,7 @@
 #include "mappers/Mapper000.hpp"
 
 Cartridge::Cartridge(Bus* bus) :
-	bus(bus)
+	bus(bus), mapper(nullptr)
 {
 }
 
@@ -17,36 +17,19 @@ Cartridge::~Cartridge()
 	delete mapper;
 }
 
-Byte Cartridge::ReadCPU(Word addr)
-{
-	return mapper->ReadCPU(addr);
-}
-
-Byte Cartridge::ReadPPU(Word addr)
-{
-	return mapper->ReadPPU(addr);
-}
-
-void Cartridge::WriteCPU(Word addr, Byte val)
-{
-	mapper->WriteCPU(addr, val);
-}
-
-void Cartridge::WritePPU(Word addr, Byte val)
-{
-	mapper->WritePPU(addr, val);
-}
-
 void Cartridge::Load(std::string path)
 {
+	// Try to load file from disk
 	std::ifstream file(path, std::ios::binary);
 	if (!file)
 		throw std::runtime_error("Failed to open file " + path);
 
+	// Read header into (temporary) structure
 	LOG_CORE_INFO("Extracting header");
 	Header header;
 	file.read((char*)&header, sizeof(Header));
 
+	// Figure out which mapper the cartridge uses and create a mapper object
 	uint8_t mapperNumber = (header.MapperHi & 0xF0) | (header.MapperLo >> 4);
 	LOG_CORE_INFO("Cartridge requires Mapper {0:d}", mapperNumber);
 	switch (mapperNumber)
diff --git a/src/Cartridge.hpp b/src/Cartridge.hpp
index 8ec968a..f210ff4 100644
--- a/src/Cartridge.hpp
+++ b/src/Cartridge.hpp
@@ -8,6 +8,9 @@
 
 class Bus;
 
+/**
+ * @brief iNES ROM header.
+ */
 struct Header
 {
 	Byte Signature[4];
@@ -21,19 +24,47 @@ struct Header
 	Byte Padding[5];
 };
 
+/**
+ * @brief Represents a cartridge and handles CPU/PPU read/writes.
+ */
 class Cartridge
 {
 public:
+	/**
+	 * @brief Add a cartridge to the Bus.
+	 */
 	Cartridge(Bus* bus);
 	~Cartridge();
 
-	Byte ReadCPU(Word addr);
-	Byte ReadPPU(Word addr);
-	void WriteCPU(Word addr, Byte val);
-	void WritePPU(Word addr, Byte val);
+	/**
+	 * @brief Read from the CPU.
+	 */
+	inline Byte ReadCPU(Word addr) { return mapper->ReadCPU(addr); }
 
+	/**
+	 * @brief Read from the PPU.
+	 */
+	inline Byte ReadPPU(Word addr) { return mapper->ReadPPU(addr); }
+
+	/**
+	 * @brief Wrote from the CPU.
+	 */
+	inline void WriteCPU(Word addr, Byte val) { mapper->WriteCPU(addr, val); }
+
+	/**
+	 * @brief Write from the PPU.
+	 */
+	inline void WritePPU(Word addr, Byte val) { mapper->WritePPU(addr, val); }
+
+	
+	/**
+	 * @brief Load an iNES file from disk.
+	 */
 	void Load(std::string path);
 
+	/**
+	 * @brief Returns the Mapper used by the cartridge.
+	 */
 	inline Mapper* GetMapper() { return mapper; }
 
 private: