What kinds of telephone cables are there?

Modular connector is the name given to a family of electrical connectors examples of which are pictured. These connectors were originally used in telephone wiring and are still prevalent for that, but are used for a variety of other things. A modular connector's advantage over many other kinds of connectors is its small size and ease of plugging and unplugging. Many uses that originally used a bulkier connector have migrated to modular connectors. Probably the most well known applications of modular connectors is for telephone jacks and for Ethernet jacks, which are nearly always modular connectors.