Plant parasitism is a biological interaction where certain plants, known as parasitic plants, derive nutrients and water from their host plants. These parasites can attach themselves to the host's tissues, often using specialized structures called haustoria to penetrate and extract resources. This relationship can harm the host, leading to reduced growth and vitality. There are two main types of plant parasitism: hemiparasites and holoparasites. Hemiparasites can photosynthesize and produce some of their own food, while holoparasites rely entirely on their hosts for sustenance. Examples of parasitic plants include mistletoe and dodder, which can significantly impact ecosystems and agricultural productivity.