Nowadays, most households have one electric iron for smoothing creased fabrics. At Market Lavington Museum, our Little Dorrit stove (see also An iron stove) had places for six irons.
In Victorian and early twentieth century times, irons relied on an external source of heat, so it was as well to have more than one iron, so that there was always one hot and ready for use. Irons also came in a variety of shapes and sizes, depending on the garment being smoothed.

These two flat irons are similar in shape, but the larger, heavier model was probably better suited to ironing large, flat items, such as cotton sheets, whilst the smaller one might have been used for garments.

Some of our irons are still smaller.

This little pair are more oval in shape and could not be left standing upright, but were no doubt handy for getting around some of the more intricate gathers and frills.

This one is different again as it is not a flat iron, but has a curved base.
All of these irons were donated along with their Little Dorrit stove and are usually displayed on that, near to the range in the museum kitchen.
Can you add anything to this or do you want to know more?