What is meant by "programming a chip" ?
What is meant by "Flashing code into a chip" ?
What are differences between these two things..??
Here chip may be microprocessor or microcontroller...
Most embedded MCUs these days have flash rewritable memory, Pics Atmel etc, as do many memory devices. Flashing is only another way of saying programming into flash memory. Usually with a dedicated chip programmer. The two terms are for the most part interchangeable. Try Googling for Pic chips as a starting point.