• Assembler is a computer program that translates mnemonic codes into computer instructions (in binary representation)
• A mnemonic helps one remember a complicated fact

  Example: to remember the names of the 5 great lakes, you
  	 can use the mnemonic HOMES
  
  	H = Huron
  	O = Ontario
  	M = Michigan
  	E = Erie
  	S = Superior
  

• The mnemonic code are also know as assembler instruction
• Example assembler instruction:

    ADD.B D0, D1     mnemonic for: add the byte operands in D0
  				 and D1 and store result in D1
  

   [label1] line1  [comment1]
   [label2] line2  [comment2]
   [label3] line3  [comment3]
   .... and so on
   end

• one assembler directive, or
• one assembler instruction (mnemonic for computer instruction)

• A directive is a command to the assembler
• Directs the assembler to "do something"
• Sample directives:
  • Tell assembler to start a program at a certain location in memory
  • Tell assembler to define a symbolic constant
  • Tell assembler to reserve space for variables
  • Tell assembler to stop assembling