updating opcodes

fundamentals3.md

@@ -13,6 +13,25 @@ The C programming is a high level language interpreted by the compiler that conv
 
 ### Opcodes and Instructions ###
 
+Each Instruction represents opcodes (hex code) that tell the machine what to do next.
+
+Three categories of instructions:
+* data movement
+* arithmetic/logic
+* control-flow.
+
+Common Instructions
+* push, pop, call, leave, enter, ret
+* mov
+* lea
+* add,sub
+* jmp,jne,jnz,jnb
+* or, and, xor
+* shr,shl
+* ror,rol
+
+Use the search page below or open the [Search Instructions](https://securedorg.github.io/x86.html) page to search for functions discussed above
+
 <iframe src="https://securedorg.github.io/x86.html" width="640" height="480" frameborder="0" style="display:block; margin: 0 auto;"></iframe>