What is data signaling formats?

Given that this question is broad, let me go to the practical answers about signalling in data communication. When sending a voice signal either through telephone, mobile or OTT; it uses a voice coding protocol like G.711 or G.729 and this type of data format is used by the sending devices and being interpreted at the receiving devices. As you recall in the OSI LAYERS those protocols are assigned in the 7th layer or Application Layer before sending the data.

For video transmission, the most common format is H.264 which is part of a wider video formats defined under MPG4 (Motion Pictures Group).

For text messaging like SMS it uses short code and 10-DLC.

10-digit long codes are often used for business communication and marketing campaigns, and require brand vetting and campaign approval via The Campaign Registry (TCR).