The typedef declaration introduces a name that, within its scope, becomes a synonym for the specified type. You can use typedef declarations to construct shorter or more meaningful names for types already defined by the language or declared by the user.
Typedef names allow you to encapsulate implementation details that may change. Unlike the struct, union, and enum declarations, the typedef declarations do not introduce new types, but new names for existing types.

The specifier typedef stands first in the declaration:

typedef <type_definition> synonym;

The typedef keyword assigns synonym to <type_definition>. The synonym needs to be a valid identifier.

A declaration starting with the typedef specifier does not introduce an object or a function of a given type, but rather a new name for a given type. In other words, the typedef declaration is identical to a “normal” declaration, but instead of objects, it declares types. It is a common practice to name custom type identifiers with starting capital letter — this is not required by the mikroC PRO for ARM.

For example:

/* Let's declare a synonym for "unsigned long int" */
typedef unsigned long int Distance;

/* Now, synonym "Distance" can be used as type identifier: */
Distance i; // declare variable i of unsigned long int

In the typedef declaration, as in any other declaration, several types can be declared at once. For example:

typedef int  *Pti, Array[10];

Here, Pti is a synonym for type “pointer to int”, and Array is a synonym for type “array of 10 int elements”.

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