We will discuss about  identifier and instructions in this chapter.

Identifier: 

Language is a medium of communication between two persons, as 

like that c language is a medium of communicate with machine and

persons. This is one way communication a programmer communicate

with machine programmer gave command to machine . If any person

learn any language then firstly he learn about alphabet then make word,

in c language every word is called identifier. In identifier we will discuss

about  constant ,variable and keywords.

Instructions:

Instructions are the combination of identifier .Instruction means giving 

command to the machine ,there will be different type of instructions like

data declaration instructions, input/output instructions ,arithmetic instruction

control instructions etc.

Collection of instructions is called Program.   

we will understand these term in  below given picture

 

so in this picture we can see that characters make identifier and

identifier makes instructions and lots of instructions make a 

Program.

In next chapter we will discuss about constants ,variable

and keywords.