Introduction To X86 Disassembly -

Suddenly, you hit a line that says CMP EAX, 20 followed by JNE 0x401050 . The machine is checking if your total is 20.

This is how a program makes a decision—like checking if a password is correct. If the numbers don't match, the "jump" sends you to an "Access Denied" screen. 4. The Hidden Vault (The Stack)

Before you look at the code, you look at your tools. Your workbench has a few small slots to hold data while you work. In x86, these are your : EAX: Your primary calculator. Introduction to x86 disassembly

To understand how it works, you have to look at the "gears" while they move. In the world of computers, those gears are and Instructions . 1. The Workbench (The CPU & Registers)

As you dig deeper, you find a "Stack"—a literal pile of data. Programs use the to remember where they were before they started a side-task. The program PUSHes its current location onto the stack. Suddenly, you hit a line that says CMP

Are you interested in or exploit development ?

This is a fork in the road. If the answer isn't 20, the machine "jumps" to a completely different section of code. If the numbers don't match, the "jump" sends

The "Instruction Pointer," the finger that points to the exact line of code currently being executed. 2. The First Discovery: MOV and ADD