The new era names, "Reiwa"
Japan has two ways to call what year it is. One is the dominical year (AD and BC) and the other is called "gengo", era names.. It has originated in ancient China and had spread to other Asian countries, but Japan is the only country today that is still using both dominical and "gengo". The gengo stays the same until the emperor passes away or abdicates from the Imperial Throne for any reasons.
The current gengo is "Heisei" which started in 1989, now 2019 is Heisei era-31, will end on April 30, 2019, and the new gengo has been selected on April 1, 2019 as "Reiwa". Reiwa era-1 will start from May 1, 2019.
Many of the shops and restaurants have already started to introduce special menus celebrating for the new gengo.