Investors allocate capital with the expectation of future returns through various assets like equity, debt, real estate, and derivatives. They include stock traders but also company owners who take on responsibilities. There are different types of investors like contrarians who buy when others sell, trend followers who invest conservatively, and hedgers who seek low-risk returns. Speculators form opinions based on incomplete evidence and include bulls hoping for price rises, bears wary of falls, stags who invest carefully in new companies, and lame ducks who are stressed bears struggling to meet obligations.