A meteor is a bright streak of light in the sky (a "shooting star" or a "falling star") produced by the entry of a small meteoroid into the Earth's atmosphere. If you have a dark clear sky you will probably see a few per hour on an average night. During one of the annual meteor showers you may see as many as 100/hour. Very bright meteors are known as fireballs - if you see one please report it.
Meteor showers are formed usually by the dust particle or debris left by comets.
As illustrated in above picture, the Preseids Meteor shower origins from Comet Swift Tuttle and we see the meteor shower radiant from Constellation Preseus, Hence the name.
One might get frustrated trying to experience a meteor shower as it is not similar to raindrops falling. Usually, a very good meteor shower would produce around 120 meteors per hour. i.e. around 2 per second. However, the meteors, though originating from a precise location, could appear anywhere in the sky as the location it enters the atmosphere and the size of the particle would be the deciding factor of whether we would be able to observe it. Usually, Meteor showers are best visible during very dark time of the night and with less light pollution - a full moon is a big negative factor to observe a meteor shower.
There are many meteor showers that occur during a calendar year and some of the famous ones happen in January, August and December. Some are listed below
January - Quadrantid Meteor Shower - Usually peaks around January 2nd
April - Lyrid Meteor Shower - Usually peaks around 22nd April
August - Preseids Meteor Shower - Peaks around 12th August
October - Orionoids Meteor Shower - Leftovers from Comet Halley - peaks around 21st October
December - Geminid Meteor Shower - One of the Brighter showers - usually peaks around 13th December
There are many more meteor showers that happen during a year and all are communicated to the alert application for the benefit of Sri Lankan public.