In C++, an object is an instance of a class. A class is a user-defined data type that holds its own data members and member functions. It is like a blueprint for creating objects. When a class is defined, no memory is allocated, but when it is instantiated (i.e. an object is created), memory is allocated.

To create a class in C++, the keyword "class" is used, followed by the name of the class. The body of the class is defined inside curly brackets and terminated by a semicolon at the end. To create an object of a class, the class name is specified, followed by the object name.

Objects in C++ are analogous to real-world entities, and they have attributes and methods. Attributes and methods are variables and functions that belong to the class. When variables are declared within a class, they are called attributes. Member functions can be used to access and manipulate the attributes of an object.

In summary, an object in C++ is an instance of a class, which is a user-defined data type that holds its own data members and member functions. Creating an object involves allocating memory for the object, and objects have attributes and methods that belong to the class.