Knowing the difference between margins and padding in Android is quite important.
Padding is the space inside the border, between the border and the actual view's content. Note that padding goes completely around the content: there is padding on the top, bottom, right and left sides (which can be independent).
Basically this is relative to your border, if you want to add the space between the elements inside the border (i.e. have the borders touching), you should use the padding property.
Margins are the spaces outside the border, between the border and the other elements next to this view. In the image, the margin is the grey area outside the entire object. Note that, like the padding, the margin goes completely around the content: there are margins on the top, bottom, right, and left sides.
If you want to add the space outside the borders (have the borders apart) you should use the margin property.
An image says more than 1000 words:
