The document discusses debentures, which are a type of loan that companies issue to raise capital. Debentures can be classified in several ways, including based on whether they are convertible to shares, secured by company assets, redeemable at a set time, or registered to a holder. Debenture holders are creditors to the company rather than owners, and are entitled to fixed interest payments but do not share in company profits/losses. Debentures provide an important means for companies to supplement share capital with long-term loan funding.