Understanding F1 car - V2: Tyres

FIA moved to a single tyre supplier in 2007(Bridgestone) but, even now, optimizing the car-tyre balance is something of a black art.
An ordinary car tyre is made with heavy steel-belted radial plies and designed for durability - typically a life of 16,000 kilometres or more. A Formula 1 tyre is designed to last for, at most, 200 kilometres and - like everything else on a the car - is constructed to be as light and strong as possible. That means an underlying nylon and polyester structure in a complicated weave pattern designed to withstand far larger forces than road car tyres.
F1 has a single tyre supplier, with all teams using identical Pirelli rubber. The advantages of this, instead of  dispose over multiple tyre suppliers, include closer racing and reduced testing and development costs.
The specifications of Pirelli tyres are differentiated by the colouring of the sidewall lettering:
super soft - red
soft - yellow
medium - white
hard - silver
wet - orange

intermediates - light blue

The racing tyre is constructed from very soft rubber compounds which offer the best grip against the texture of the track, but wear very quickly in the process. Over 150 different components are used in the manufacture of F1 tyres but the main ingredients are rubber, carbon and mechanical oil. Varying the relative amounts of these three components will produce different tyre compounds, which will each have different characteristics.  If you look at a typical track you will see that, just off the racing line, a large amount of rubber debris gathers. All racing tyres work best at relatively high temperatures.

Harder compound tyres will be more durable than softer compound tyres, meaning that the driver can complete a greater number of laps before the tyres lose performance and they are forced to make a pit stop. The harder compounds will provide less grip than the softer compounds, meaning that the driver will not be able to go as fast on each of the laps they make. The choice of tyre compound is therefore a compromise between durability and grip. Choose hard and you'll be able to stay out longer than your competitors. Choose soft and you'll have to pit earlier in the race but you'll be going faster than they are and may be able to make up the difference. The physical explanation of the difference between the hard and soft compounds is the degree to which the rubber molecules interact with the track surface.

SLICKSlick tyres are the ones that F1 drivers use most of the time. A normal slick tyre actually has no tread pattern at all. This is because in dry conditions the aim is to get the maximum grip from the tyre and this is achieved by having as much rubber in contact with the racetrack as possible.

WET
The wet tyres, which are characterised by grooves in the tread pattern, come in two types: full wet tyres, for rain, and intermediates and the two tyres have in common the same compound.
The wet tyres have deep grooves in them, with channels designed to expel water on full wet asphalt. These tyres are similar to a road car tyre, and are designed to expel more than 60 litres of water per second at 300kph. A road car tyre can only displace about 10 litres of water per second, at much lower speeds.
INTERMEDIATE
Intermediate tyres are exactly what their name suggests - a compromise between a full wet and a fully slick tyre. They have slightly shallower grooves that are cut in a different pattern and remove a fair amount of water from the racetrack surface while also providing a decent level of grip once the track has dried. These are the tyres that are used most often when weather conditions are bad. Only in absolutely torrential conditions where there is continuous rain are the fully wet tyres needed.