Make one application talk to another in VB

[Designer]

I am going to use a program to read values from another PC, this will be running in the background, with another program running in the foreground, these programs must run separately as if a problem occurs in the data gathering program it will not affect the program in the foreground.

I need to generate some form of conformation signal from the background program that can be read by the foreground program to determine if the data gathered in the background program matches specific value.

How is the best way to go about this? Sorry if i've rambled a bit but i wasnt quite sure how to word this problem. Using Visual Basic 6. The simpler the better as i'm not very experienced with VB.

Thanks