Objects, Types, and Values

An object is a part of system memory of particular type that tells what kind of information is stored in it. A named object is called a variable. A statement that introduces a new name into a program and sets aside memory for a variable is called a definition. The data items we put into variables are called values. The input operator >> (get from) is sensitive to the type of variable we read into. Reading of strings is terminated by whitespace, which is a space, newline, and tab characters.

int i = 34; // integer
double d = 3.4; // double-precision floating-point number
char decimal_point = '.'; // infividual character
string name = "Roman"; // character string
bool tap_on = true; // Boolean

Initialization always finds the variable empty. Assignment, on the other hand, must clear out the old value from the variable before putting in the new value.