This is for you Lori: Mentha (commonly known as mint) is a genus of around 25 species. It's often found in wet or moist soil and has lance-shaped to rounded leaves that can be light to dark green, purple or blue-grey. Flowers appear in the summer at the end of the branches.
Mint smells great, it can be used in the kitchen or in cocktails (my favourite is with Pimms). Its flowers attract bees (which is a good thing except if you plant it near a terrace or near a child's playarea) and dries well and can be used in pot pourri. It's a perennial plant which means it comes back year after year.
It can be grown in a vegetable or herb garden, is useful for ground cover, good in rock gardens and can be used by the side of ponds to stabilise the muddy edges. It's also easy to propagate and cuttings will root at any time during the growing season. And it can be grown in shady spots or full sun.
So far, so good! The downside is that mint is super invasive. I have some but I didn't plant it myself - it's travelled under a hedge and under a wall from my neigbour's garden. You can restrict the spread of invasive types of mint by planting in deep containers and burying them in the soil or by growing in small beds, which restrict the roots. There are some types of mint that are less invasive than others, check the label when you buy. It's fine grown in containers of course although they will look bare in winter when it disappears.
I tend to chop the flowers to keep the leaves large and the branches less spindly.
In France, Corsican mint (mentha requienii) is popular for borders, paths and rock gardens. It has glossy bright green leaves with a strong peppermint smell which release a scent if they are brushed against, so it's nice at the edge of borders where you might brush against it.