Assigning a variable its first value is called initializing the
variable. When you declare a variable in C, you can also initialize it
at the same time. This is no more efficient in terms of a running
program than doing it in two stages, but sometimes creates tidier and
more compact code. Consider the following:
int initial_year;
float percent_complete;
initial_year = 1969;
percent_complete = 89.5;
The code above is equivalent to the code below, but the code
below is more compact.
int initial_year = 1969;
float percent_complete = 89.5;
You can always write declarations and initializers this way, but you may
not always want to. (See Style.)
