A credit score is a crucial financial metric influenced by payment history, amounts owed, credit history length, new credit, and credit mix. Improving it involves timely payments, low credit utilization, keeping old accounts, and wise credit applications. Harmful practices include late payments, high balances, closing old accounts, and excessive credit applications. Regular credit monitoring, budgeting, and professional advice are key to building good credit habits. Maintaining a good score is a continuous process, leading to better financial opportunities.