I have created a custom Object in Salesforce. Now to save values in that what should i use Page layouts or a visualforce page and apex controller? in other way- When should we use page layouts and when the visualforce pages should be used?
Page layout is a built-in standard mechanism for displaying information to user. You can use Page layout editor without any development experience, just drag-and-drop. If you need a simple form which just shows field value and related records you have to use a page layout. But sometimes you need to use JavaScript, custom HTML tags, CSS on you page in this case you have to use VisulaForce pages which are similar to JSF or any similar technologies. Also note that you can include VisualForce inside standard page layouts.