Method vs. Subroutine

Attribute	Method	Subroutine
Definition	A function or procedure associated with a class	A set of instructions that performs a specific task
Usage	Used in object-oriented programming	Used in procedural programming
Return Value	May or may not return a value	Does not return a value
Visibility	Can be public, private, or protected	Not applicable
Invocation	Called using dot notation on an object	Called by name

Definition

A method is a function that is associated with an object in object-oriented programming. It is a piece of code that can be called by name to perform a specific task. Methods are used to define the behavior of an object and are typically called using dot notation. On the other hand, a subroutine is a sequence of instructions within a program that performs a specific task. Subroutines are standalone procedures that can be called from anywhere within the program.

Scope

Methods are typically defined within a class and are used to manipulate the data of that class. They have access to the data members and member functions of the class. Subroutines, on the other hand, are standalone procedures that can be called from anywhere within the program. They do not have access to the data members of a class unless they are passed as parameters.

Return Value

Methods can return a value to the calling code using the return statement. The return type of a method is specified in its signature. Subroutines, on the other hand, do not return a value by default. If a subroutine needs to return a value, it must do so using output parameters or by modifying global variables.

Arguments

Methods can take arguments as input parameters to perform their tasks. The arguments are specified in the method signature and can be of any data type. Subroutines also take arguments as input parameters, but they can also have output parameters that are used to return values to the calling code.

Encapsulation

Methods are encapsulated within a class and are used to define the behavior of that class. They can access the data members and member functions of the class. Subroutines, on the other hand, are standalone procedures that are not associated with any specific class. They do not have access to the data members of a class unless they are passed as parameters.

Reusability

Methods are reusable blocks of code that can be called from anywhere within the class. They can be called multiple times with different arguments to perform different tasks. Subroutines, on the other hand, are standalone procedures that can be called from anywhere within the program. They can also be reused, but they are not associated with any specific class.

Overloading

Methods can be overloaded, which means that multiple methods can have the same name but different parameters. The compiler determines which method to call based on the number and types of arguments passed. Subroutines, on the other hand, cannot be overloaded. Each subroutine must have a unique name within the program.

Visibility

Methods can have different access modifiers that control their visibility within the class and outside the class. The access modifiers include public, private, protected, and package-private. Subroutines, on the other hand, do not have access modifiers. They are visible to all parts of the program unless they are declared as private.

Inheritance

Methods can be inherited by subclasses in object-oriented programming. This means that a subclass can use the methods of its superclass without redefining them. Subroutines, on the other hand, cannot be inherited. Each subroutine must be defined within the class where it is used.