Implementations relate to prioritized data transmission features over networks. A method can include deriving description data from content data. The description data describes content of the content data and includes one or more portions corresponding to one or more portions of the content data. The description data is transmitted to a destination over a network to be made accessible over the network at the destination to one or more users. The content data also is transmitted to the destination to be made accessible. At least one portion of the description data finishes transmitting and is made accessible before its corresponding portion of the content information finishes transmitting and is made accessible.