Geckos are harmless and live on insects. They are widely scattered over the warm parts of the earth and one kind, Brooks' gecko, which originally lived in West Africa, has found its way round the world by hiding away in bales of produce on ships. Some find their way to Britain.
When people talk about grasshoppers they usually mean the common insect of the English countryside that chirps throughout the long summer days and uses its long, thick hind legs to hop about in the grass. They can become serious pests to plants and crops.
Although no crane flies are harmful to humans they can be rather annoying and troublesome. These are the ones that live in the grass or grassy places and usually come out at night. They cannot fly very strongly.