What do you mean by typedef?

Answer 1

Quoted: "Typedef is a keyword that is used to give a new symbolic name for the existing name in a C program". Read the details at the following link:

https://fresh2refresh.com/c-programming/c-typedef

Hth, cmiiw

Answer 2

It basically renames a type. It is useful when there is some variable with a primitive data type (int,char,float,...) but the content is not meant to be interpreted by us as a N-bit number (as the datatype suggests) so you may want to rename the data type to something you understand.

For example, a char data type could store the red channel of a pixel of some image, but also the blue one so you may get confused with so much chars. Then, you could do something like

typedef char REDNESS;
typedef char BLUENESS;
typedef char GREENNESS;

and then use them as regular data types, like so

REDNESS pixRedVal = 255;
BLUENESS pixBlueVal = 255;
GREENNESS pixGreenVal = 255;