Difference between Local I/O and Remote I/O

What is the difference between Local I/O and Remote I/O.If the difference just the area location then its mean normal I/O card can also be used as Remote.

Then how we can differentiate between Normal I/O Card,Flex I/O and Point I/O.

Local connects directly to the CPU
remote I/O is usually fed by some form of bus protocol and is locate away from the main CPU panel

Local I/O generally means that it's in the same chassis as the processor and is accessed through the back-plane.

Remote I/O is just that, it's just I/O with no processor that is remote from the local chassis. It will have some sort of remote I/O (RIO) scanner or adapter to handle the communications with the processor or remote I/O adapter in the local chassis.

Yes,regular I/O hardware can be used remotely.

Flex I/O is an Allen Bradley modular remote I/O system that can be used with most any AB platform and RIO Protocol. It can be readily identified by sight.

have a look at Visilogic (Unitronics)
the HMI is the CPU but the I/O expansion rack could either be remote or local
so depends on how you look at it