The article "Davies - Principles of Tax Law" covers various aspects of tax laws, including income taxation, capital gains tax, inheritance tax, and value-added tax. It provides insights into handling taxes, assessing income, and understanding different types of income like trading, property, and employment income. The article also discusses the taxation of trusts, estates, individuals, and companies. Additionally, it delves into capital gains tax, inheritance tax evolution, and value-added tax rates and exemptions.