| Data types | Qualifiers | User-defined | Storage Classes | Loop | Decision | Jump | Derived | function | Other |
| int | signed | enum | extern | for | if | goto | struct | void | const |
| char | unsigned | register | while | else | continue | union | return | volatile | |
| float | short | static | do | switch | break | sizeof | |||
| double | long | auto | case | ||||||
| default |
Brief introduction of standard keywords and their specification:
Data type Keywords:
| int | Specifies the integer type of value a variable will hold |
| char | Specifies the character type of value a variable will hold |
| float | Specifies the single-precision floating-point of value a variable will hold |
| double | Specifies the double-precision floating-point type of value a variable will |
Qualifier Keywords:
| signed | Specifies a variable can hold positive and negative integer type of data |
| unsigned | Specifies a variable can hold only the positive integer type of data |
| short | Specifies a variable can hold fairly small integer type of data |
| long | Specifies a variable can hold fairly large integer type of data |
Loop Control Structure Keywords
| for | Loop is used when the number of passes is known in advance |
| while | Loop is used when the number of passes is not known in advance |
| do | Loop is used to handle menu-driven programs |
User-defined type Keywords
| typedef | Used to define a new name for an existing data type |
| enum | Gives an opportunity to invent own data type and define what values the variable of this data type can take |
Jumping Control Keywords
| break | Used to force immediate termination of a loop, bypassing the conditional expression and any remaining code in the body of the loop |
| continue | Used to take the control to the beginning of the loop bypassing the statements inside the loop |
| goto | Used to take the control to required place in the program |