Based upon where you are from, different countries have different terms for "storm drain". abc

Subject to where you are from, different countries have different terms for "storm drain".
Accordingly to Wikipedia, a storm drain is actually a tunnel that carry runoffs (rain) from urban areas. For a layman, it helps to think along the line of sewage system that functions beneath our cities.
In the states, this is best known "storm drain" or "storm sewer".
In great britan, this is commonly known as "surface water drain" or "surface water sewer".
In Australia and New Zealand, it is also known as "stormwater drain".
And there it is, the next time you hear someone mentioning "storm drain", "storm sewer", "surface water drain","surface water sewer" and "stormwater drain", you now know they refer to exactly the same thing.
Functions of storm drain include draining excess water ( Jonite tree grill or storm water) and ground water from pavement, streets and carparks into rivers and streams to protect yourself from flooding.
Although storm drains accomplish a amazing job of draining excess water from the urban areas, the inlets are essentially openings where left uncovered can pose a danger to pedestrians. Left uncovered, rubbish will get into the storm drains and cause choking which can eventually trigger flooding.
In order to ensure storm drains serve their purposes while minimizing the dangers posed to pedestrians and to prevent choking of the drains, drain covers (gratings) are employed to cover the inlets (openings) of the storm drains to accomplish the two purposes.
Over at Jonite, we concentrate on steel reinforced drain covers (gratings) which cover your storm drains while preserving the aesthetic components of the architecture around the drain covers.