Shintoism

This is probably usually associated with the large shrines that most tourists see in Japan. But what fascinates me is the many small shrines that appear to be near every home especially in the countryside. The entrance to most shrines is usually associated with one or multiple torii or gates consisting of two upright posts and two horizontal beams frequently painted orange. But there are many much more obscure shrines some with a vase of flowers, a green tea cup and not much else. What is the purpose of these shrines? I suspect that they are a means of offering thanks for everyday blessings and are apparently also used to ask for aid from the spirit world or kami.