www.dulux.co.uk/en/decorating-tips-and-advice/dr-dulux-paint-finishes-explained
Choosing the right sheen level can completely transform the look of your walls, so make sure you consider different finishes to make the most of your space. Here's a little guide to help you:
Matt emulsion is smooth, velvety and helps to hide imperfections on less-than-perfect walls.
Flat matt emulsion is even more velvety and because matt surfaces don't reflect light, they make all colours look as similar as they can be in very different light conditions. Flat matt works wonders on deeper shades, too.
Satin and Silk are 'mid-sheen' finishes, which means they look like a slightly polished surface and reflect a bit of light. Silk is a finish associated with walls and satin for woodwork. You can wipe silk wall finishes easily which makes them very practical but if you have less-than-perfect walls, all the lumps and bumps may show up a bit more. A satin finish on woodwork helps to hide imperfections and gives colour a softer appearance.
Eggshell has less of a sheen than silk or satin and it does look like the surface of an eggshell (the clue's in the name). It sits somewhere between matt and a silk finish and gives a beautiful classic look to woodwork – and can also be used on walls when you want a heritage style look with a tough finish.
Gloss is a shiny finish designed for woodwork and it reflects lots of light – so is perfect for paler colours. You have to have a great surface to make it look its best, but it is hugely practical and adds a lovely contrast to walls that are painted in a matt.