Mumbai, May 22 -- Pneumatic tyres are those, which operate with pressurized air or with 'inflation pressure' . They are all classified as bias tyre, radial tyre and bias belted tyre based on their design and constructions.

There are, however, other two tyre categories that do not require inflated air pressure. They are classified as non-pneumatic tyres such as Solid Tyre and semi-pneumatic tyre .

Solid tyres are different than airless tyres but this category does not require to be inflated. They are fitted directly to the metallic rim for operation.

Earlier, automobiles rolled on tyres of solid rubber until people realised that pneumatic tyres absorbed shock more effectively. Solid tyres are being made these days with highly engineered...