Text files, mainly. The name of the files usually ends with .C and .H (lowercase in unix).
the master program of OS is stored in ROM.
a program that is stored in the memory of the computer that executes it
The concept of stored program was presented by Dr.John Von Neumann.
Memory.
By stored-program computer, we mean a machine in which the program, as well as the data, are stored in memory, each word of which can be accessed in uniform time. Most of the high-level language programming the reader.
Von Neumann
ROM
bill gates
Yes. Java program data can be stored in RAM, in a file, sent across a network, or however else you (the programmer) wishes it to be stored.
A Backup
Memory, disk, tape... it depends.
John Von Neumann.