Customised transaction codes

Question

Hi,
I have seen that in projects, there are customised T codes for standard transaction. My questions are:
1) what is the need for the customised T code (z tcode), when standard is available in system.If the purpose is to modify screens, then one can use screen exits and run standard t codes only. Can somebody explain with a business scenario for SD module regarding the need for customised T codes?
2) Do customised tarnsactions are made to control authorisations . If yes, then why the need when the authorisation can be controlled in standard T codes ?
3) Is making a customised T code same as making an area menu ?
4) How the customised T code is made. What is the user exit availiable etc ? what functional specs do a functional consultant needs to give.
regds

Answer 1

what is the need for the customised T code (z tcode),
When the standard TCode does not address the requirement, we have to go for zee tcode
Do customised tarnsactions are made to control authorisations
Yes while creating any zee TCodes, most probably, you would be copying the standard program.  So based on that object, authorization can be controlled
How the customised T code is made
With the help of ABAPer
What is the user exit availiable etc
Certain requirements cannot be addressed through standard copy controls.  So in that case, you have to apply user exit.  For example, in sale orders, let us assume, your requirement is schedule line cannot be pre dated by end user, you have to go for user exit.
thanks
G. Lakshmipathi