Capsicum annuum is characterised by the fact that the smaller the fruit the hotter the taste.
Some larger ones are generally quite mild and sweet - but beware of the small ones - particularly the seeds, which are the hottest part.
Capsicum annuum has soft but erect stems and branches with deep green, smooth leaves and small white flowers that mature to bell shaped hollow fruit in yellow, green, orange and red.
The larger and sweeter ones are excellent when eaten raw as part of salads but also roast well and can be stuffed and baked to great effect as well.
The smaller and hotter ones are best used in cooking only.