title: What does the following byte specifier for adding to a memory reference does in NASM assembler?
body: <p>The following code</p>
  
  <pre><code>section .data
  
  Snippet db "KANGAROO"
  
  section .text
  
  global_start
  
  _start:
  
  mov ebx, Snippet
  add byte [ebx], 32
  </code></pre>
  
  <p>is adding 32 to the number to which the memory address in BX refers to. However, what is the byte specifier after add? My book says that it means that we are only writing a single byte to the memory address in EBX. But I don't quite understand what that means (I am a beginner in assembler). What does it mean to write a byte to a memory address? What would it mean to write more than one byte?</p>