Although tiles may be made of a vast range of materials, the most common type are straightforward ceramic wall tiles, which usually come in square sizes, among the most common being the six-inch square. Ceramics have been used by human beings for thousands of years and continue to be used in a wide variety of applications. They are, for example, typically resistant to heat and perpendicular shock. That's why ceramic tiles are used to spacecraft to protect them during re-entry into the Earth's atmosphere, and also in some sophisticated forms of modern tank armour.

A ceramic is basically a mineral that has been created or dug out of the ground in a damp, pliable form and which is then 'fired' to give it strength and help form the glaze. In any tile, the glaze is typically the strongest and most resilient part of the structure, and is created by brushing silicate powder on to one face of the tile before it is fired. The 'glassy' surface of a glaze is made of exactly that - glass - albeit glass that's deeply bound to the underlying fabric of the tile. The inside of the tile is called the 'biscuit', and can vary in colour, strength, weight and texture depending on the material used to make the tile. One thing to look out for when buying cheap tiles is that the colour of the biscuit isn't darker than the colour of the glaze. Cheap tiles tend to have thin glazes, so a knock or scratch, or simply wear and tear, could leave the dark biscuit underneath showing through.

Glass is similar to ceramic, and, given the right treatment, can have properties nearly as strong. Glass tiles are gaining in popularity, although the tricky and dangerous business of cutting them is generally considered a job for an expert. Because of glass's propensity to shatter, glass tiles need to be fixed with the utmost care and expertise, keeping cutting to a minimum and using a glass-appropriate adhesive and grout.

Grout itself comes in lots of different varieties. If you feel like a change from plain-vanilla off-white grout, coloured grouts are available. If you decide to use a coloured grout, try to get a chance to see the particular colour you've chosen in situ with some tiles. Although colour fixing in such products is generally good, coloured grout can dry to a slightly different colour than expected. It also has a pretty bad reputation for staining the glazed surface of tiles. If you're using this sort of grout, make sure that you polish off any excess from tile surfaces very quickly after the initial fixing is done.

If you really want a bathroom that's the last word in luxury and decadence, you could consider mosaic tiling. Mosaics were out of fashion in British bathrooms for quite a while - about sixteen hundred years, to be exact - but recently they've made a bit of a comeback in popularity among homeowners who have a bit more to spend on their bathrooms. Back in Roman times mosaic was usually laid using normal clay ceramic tiles. These days, glass mosaic tiles are much more popular for their durability and sheen. There are a number of glass mosaic companies in the UK dedicated providing bathroom mosaic work, and most offer a choice of off-the-peg and bespoke designs to suit your bathroom and your budget.