What is a Coffee Dripper?
For centuries, people around the world made coffee by heating ground coffee in a pot with water, as in the Saudi Arabian and Turkish traditions. Then the percolator, which brews coffee by continually cycling the boiling brew through the grounds, was invented around 1810. It became a standard brewing method in Europe. The espresso machine came soon after.
But in the 1900s, a German woman named Amalie Auguste Melitta Bentz was dissatisfied with the taste of percolator coffee and the grounds left behind in her cup. She started to prototype alternative brewing methods and came up with a technique using blotting paper and a can that she punctured with a nail.
The resulting brew was less bitter than percolator coffee and satisfyingly free of grounds. In June 1908, Amalie filed a patent for the paper filter and the Melitta company was established.
Metal drippers have a low thermal mass which means they heat up faster and reduce the chance that the dripper "steals" the heat away from the grounds. But they have low heat retention so it will release the heat faster than others. Metal drippers usually have quite good durability depending on the brand and price of the dripper itself.
Ceramic and Glass
Ceramic and Glass have a quite high thermal mass which can steal the heat away from the grounds to heat itself up. This can be prevented by pre-heating the dripper before using. Ceramic and glass have a high heat retention which makes the extraction from start to finish more even. The durability is not the best, and the price is usually quite high.
Plastic has a low thermal mass and high thermal retention which makes it the most stable. This is the cheapest option compared to others. I personally avoid using plastic drippers because it tends to give the coffee plastic like aftertaste.
Usually there are 2 variants which are size 1 and size 2 drippers. Size 1 usually for 1 portion and size 2 are for 2-3 portions.
There's a lot of shapes but I will explain to you a few famous one.
Shapes like cones with steep angles encourage faster flow rate. This makes you can control the turbulence better and control how fast or slow the extraction is going. One of the most famous brand that fell into this category are Hario V60.
One of the oldest dripper designs. The flat bottom and singular hole makes the extraction even, the singular hole and flat bottom prevent channelling and turbulence in the coffee bed.