What is the difference between using 叫　and 叫做　？
叫= to call / be called


我叫彼得 could mean: 


'I call Peter (e.g. I make a phone call to Peter) ' 
'I am called Peter (my name is Peter)' 



  叫做 = be called as 


我叫做彼得 = I am called as Peter (my name is Peter) - no ambiguity here


  称= [1] [v] call; name; term; address as
  [2] [v] say; state; express; claim



人称(为) = people call (him/ her/ it) as
自称(为) = call oneself as / self proclaim as
称为 = be called as


Abe Shudug wrote:


  Could you please also clarify how it becomes him/her/it with 人称为 ? Maybe an example sentence..do you mean 他　她　它　　ｎｅｅｄ　ｔｏ　ｂｅ　ａｄｄｅｄ?　　Ｏｒ　为　serves that function ?? 


Some examples:

(他/她)被人稱為天下無敵 = (他/她)人稱天下無敵

被人稱為 is often shortened to 人稱

(他/她)自稱為天下無敵 = (他/她)自稱天下無敵 

自稱為 if often shortened to 自稱

[他/她/它] is the object, which is needed in a complete sentence. 

为 acts as the conjunction 'as'(without antecedent) in the degree, manner


  称为 is more literal;  叫做 is more colloquial