Besides the Obligatory and Essential Prayers, the Holy Prophet (PBUH) used to make arrangements for the Voluntary (Nawafil) Prayers too. It is mentioned in the Hadith that Voluntary Worship is a means of attaining proximity to Allah.
It is better to offer Sunnah and Voluntary Prayers at home – however it is better to offer Taraweeh, Tahiyat ulMasjid (Prayers offered as a mark of respect upon entering the mosque), and the Voluntary Prayers upon returning from a journey, in a mosque. If preoccupation or lack of interest or laziness prevents one from offering these Prayers at home, then these should be offered in the mosque.