Cannot find packet data in Samsung Galaxy S Where can I can find 'packet data' on my phone, and how can I use internet when I'm on the road?
You must be referring to Mobile Data. Take note that using mobile data on the road will incur data charges per minute or per data size (consumption), depending on your plan.

In the Samsung Galaxy S4, mobile data can be enabled in Settings &gt; Connections &gt; More networks &gt; Mobile networks &gt; Mobile data. You can also find a Mobile data quick-switch in the quick settings section of the notification panel. See if you can find something similar for the Samsung Galaxy S. With this checked, you can now surf the internet using your phone.