Data in C

by Amit

In C, the data you use in your programs will usually fall into one of the three
basic categories: int, char and float. Data in C has no
existence without an associated memory location labeled by an
identifier, usually referred to as a variable (the term variable
is a bit misleading, since it essentially means that it must always
vary, but you can have constant variables – i.e. variables whose
values do not vary). Considering this and C’s requirement for static
, a variable declaration statement is required before data
can be stored in a variable. This declaration statement usually takes the
form of data-type var-name [= value], where the =value part may
or may not be present. For example, the statement int a=1;
declares a variable a which will store integer data and stores
1 in it. What this statment basically tells the C compiler is
that it should allocate a block of memory large enough to store an
integer and it will referred to as a. It is possible to obtain the
address of this memory location using the & operator.

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