This article is first part of a two part article for people  who want to start writing socket programming with VB. This example uses an ocx component that comes with VB. You  will need a from with a command button (command1), a socket  component (winsock1) and a listbox (list1). We will need to do the following steps to have our hello  server running. 1- We must bind TCP/IP socket to port 1024 when form loads. 2- When we press Listen Key (command1) socket starts     listening port 1024. In this way program will be able to     accept connections. Listening socket is usually used for     just receiving TCP/IP connections. It will also queue     them until our program is free to serve them. We will     usually need another socket to service connections that    has been queued. However as we want to create a small     server we will use a single socket for both listening     and communication with client programs. 3- When a socket on a remote program opens a connection to     our program, a Connection request event is triggered and     ConnectionRequest subroutine is automatically called.    In this subroutine we can accept the connection. 4- Now that everything is prepared, whenever an accepted     socket tries to send us data another event called     DataArrival will be triggered. When we receive this event     we first read data that is sent to us and show it in a     listbox and then send a 'hello' string back to the client     program connected to us. This is why we call this server     a 'hello' server.  5- After sending data, server has no reason to keep     connection so it must close the connection.    When sending data is finished, a SendComplete event is     triggered. As we want to accept more connections we close     socket and then call listen function again to be ready     for accepting other incoming connections. 6- If any error occurs on socket an 'onerror' event is     triggered. In this case we will display an error message. And now program source: Private Sub Command1_Click()   Winsock1.Listen End Sub Private Sub Form_Load()   Winsock1.Bind 1024 End Sub Private Sub Winsock1_ConnectionRequest(ByVal requestID As Long)   If Winsock1.State <> sckClosed Then Winsock1.Close   'Load Winsock1(newInstanceIndex)   Winsock1.Accept requestID End Sub Private Sub Winsock1_DataArrival(ByVal bytesTotal As Long)   Winsock1.GetData a$, vbString   'received data is in a$ , you can use it   List1.AddItem ("Received : " + a$)   Winsock1.SendData "hello" + vbCrLf   'The string 'hello' is sent in answer to client request   List1.AddItem ("Sent : Hello") End Sub Private Sub Winsock1_Error(ByVal Number As Integer,              Description As String, ByVal Scode As Long,             ByVal Source As String, ByVal HelpFile As String,             ByVal HelpContext As Long,             CancelDisplay As Boolean)   MsgBox "Error in Socket" + Description, vbOKOnly, "Error" End Sub Private Sub Winsock1_SendComplete()   Winsock1.Close   Winsock1.Listen End Sub 7- Server written in this article can serve one connection     at a time. If you want you can use more connections by     loading new sockets for each incoming connection. In next part of this article we will write a client side  program for this server.  Client program will connect server program over network and  will receive 'hello' string and then connection will be  closed by server program. You can test this program by  connecting to port 1024 using a telnet program. Whatever you send to it, server will answer with a 'hello'. If you need codes for this article you can visit our site  and go to ezine page. There you will find a link to zipped  source files.