Du pain

Hi Hà Thu,

You would say -

'du pain' for the generic item which is known as bread but you could say, 

'des petits pains au chocolat' for some countable items like these which come in the shape of small loaves.

Hope this helps!

Hi Sandra,

You would only use 'le pain' to say the one you are talking about.

For instance, from a list, you would say-

"Toi, tu achètes le pain, moi,  le fromage, etc. = You buy the bread, I buy the cheese etc.

Hope this helps!