There are three main operators, based in Cairo, that mostly form a network that covers all of Egypt.

They are as follows:

The Upper Egypt Bus Company. It covers all points along the Nile valley, as well as the Fayoum and Inner Oasis and the Red Sea coast e.g. Hurghada, Safaga and Marsa Alam
The East Delta Bus Company covers the Sinai Peninsula and the Canal Zone.
The West Delta Bus Company serves Alexandria, north coast, Siwa Oasis and the Nile Delta towns.
The El-Gouna Bus Company. Their buses cover Hurghada, Safaga and Marsa Alam
If you want to check Egypt bus service schedule, click here
The Super Jet Bus Companies: they cover most of egypt and their stations are located in Almaza (Heliopolis), Turguman Square (Tahrir), Giza, and Cairo Airport. if you need to call them Tel: (002)-(02)266 0212 .