You use a button's Text property (formerly the Caption property in VB6 and before) to set its caption. This property is available at both design time and run time. After you add a button to a form, you set its caption by placing the appropriate text in the Text property in the properties window:
Private Sub Button1_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles Button1.Click Button1.Text = "You clicked me!" End Sub
It's useful to be able to change the caption of buttons. For example, if a button's caption reads "Connect to Internet", then, when connected, you could change the button's caption to "Disconnect from Internet", and disconnect from the Internet when the button is clicked.