Hello. I'm building an obstacle avoiding robot car and have some questions. I use an Arduino sensor shield (V5.0), and I want to know what is it good for ? I've searched and knew that it's good for wiring but I have to know what it is exactly good for. Is it because of Servo motor ? Because I know I can build the robot with Motor shield or even without any shields but I had to use sensor shield, so I would appreciate if you can help me.
@ahora, I have suggested to the Moderator to move your question to its own Thread as it seems quite different from the discussion in this old thread.
Also, it seems that your question is about an Arduino Sensor Shield rather than an obstacle avoiding robot.
...R
@ahora DO NOT HIJACK other people posts.
Split topic.
Thanks R2.
ahora:
I use an Arduino sensor shield (V5.0), and I have to know what it is exactly good for. Is it because of Servo motor ?
According to Terry King in reply #10 here, there are various sensor shields all called V5, so first you need to know which one you have 
The one he talks of there has a jumper which you can remove to allow you to provide external power to the shield, so then yes, it would be a good way to power servos. That the shield has male connectors is, I think, likely to provide more reliable connections that sticking male pins into Arduino females.
And for using sensors (and servos, if you have external power as above), I think it's very handy to have G, V and S all available for each Arduino pin; that will save messing around with breadboard to get power rails.
(But do you have the one he's talking of?)
but I had to use sensor shield
I'm curious: why?