service agreement. A contract entered into for a contractor to provide some form of useful task for their employers in return for compensation. A service agreement can also be a feature offered along with a warranty for a product for the manufacturer to provide service or coverage of any costs of service in case the product malfunctions during a given period.
Euridice (1600) is the first surviving opera. The libretto was by Rinuccini, music by Peri, with some portions by Caccini. This was also significant in that it used recitative, a foundation of operatic storytelling. But--what was the first great opera? My vote is for Monteverdi's Orfeo, libretto by Striggio, premiered in 1607.
Baroque opera (1600-1750) The first opera ever written was performed in 1597 in Florence in Italy. It was called Dafne and the composer was Jacopo Peri. This opera is now lost, but three years later, in 1600, he worked together with another composer called Giulio Caccini to write an opera called Euridice. The music for this still exists. It was nearly all recitative.