A company's accounts come as three tables, and each answers its own question. The income statement shows what the company earned over a period: revenue at the top, costs below it and net income at the bottom, which is what is left for shareholders after tax. When revenue grows and net income does not, costs are growing faster, so it is worth finding out which line has moved.
The balance sheet is a snapshot on a single date: what the company owns and what it owes. Assets equal liabilities plus shareholders' equity. Debt is best judged against cash and earnings rather than on its own, because the same amount can be unremarkable for a large company and dangerous for a small one. Note that a balance sheet is published every quarter, so its date is often more recent than the date of the annual income statement.
The cash flow statement shows how much money actually came in. Net income is an accounting figure, while operating cash flow is what the business really collected. A healthy company usually brings in at least as much in cash as it reports on paper. Out of that flow it pays for equipment, pays dividends and buys back its own shares.
Every column carries the date its period ended, because companies close their financial years in different months. A dash means the company did not report that line, not that it equals zero: a bank, for example, has no cost of revenue. Annual figures give the overall picture, and quarterly ones reveal a turning point sooner, although they are more seasonal, so compare a quarter with the same quarter of the previous year.