Translations:Code snippets/3/en

There are a couple of concepts to know when designing interface:
 * Modal/non-modal dialogs: A modal dialog appears in front of your screen, stopping the action of the main window, forcing the user to respond to the dialog, while a non-modal dialog doesn't stop you from working on the main window. In some case the first is better, in other cases not.
 * Identifying what is required and what is optional: Make sure the user knows what he must do. Label everything with proper description, use tooltips, etc.
 * Separating commands from parameters: This is usually done with buttons and text input fields. The user knows that clicking a button will produce an action while changing a value inside a text field will change a parameter somewhere. Nowadays, though, users usually know well what is a button, what is an input field, etc. The interface toolkit we are using, Qt, is a state-of-the-art toolkit, and we won't have to worry much about making things clear, since they will already be very clear by themselves.