Interior eggshell paint is a great choice for areas that need more durability, such as kitchens and bathrooms. Eggshell (and satin paints which the term is used interchangeably) have a slightly higher sheen than your standard flat matt emulsion paint, so picks up less dirt and grime. However, plenty of people use eggshell as a normal wall emulsion interior paint regardless. These can also be used as an eggshell finish for wood and trim, or for rooms where you just want to use one type of paint for all walls, ceilings and trim. 

I like to use the Auro 517 eggshell paint for my interior window frames, skirting boards and cupboard doors, or the Grafclean Eggshell which is pretty similar, just a different colour range. Both great, and both I have personally used.