Accounting Basics

This deck offers a friendly introduction to the foundational concepts of accounting, making it a great starting point if you are new to the subject. It walks through core ideas such as what accounting is, the main branches of the discipline, and the key users of financial information. You will also encounter the building blocks of the field, including the accounting equation, double-entry bookkeeping, assets, liabilities, owner's equity, revenue, and expenses.

The cards are well suited for students beginning a course in accounting, small business owners who want to understand their own books, or anyone considering a career in finance or bookkeeping. They also touch on important frameworks like GAAP and IFRS, giving you a sense of how accounting rules are organized around the world, as well as practical tools like the chart of accounts, journals, and the general ledger.

Because accounting concepts build on one another, try working through the deck in order rather than jumping around randomly. Each new term often relies on something you learned a few cards earlier, so a steady pace helps the pieces connect into a clear picture. Revisiting earlier cards as a warm-up before each new study session is a simple way to strengthen your recall over time.

Take your time with each question and try to phrase the answer in your own words before flipping the card. This active approach turns the flashcards from a quiz into a real learning tool and helps you remember the language of accounting long after you have finished the deck.

Accounting is the process of recording, summarizing, analyzing, and reporting the financial transactions of a business so that useful information becomes available for decision-making. Often called the language of business, accounting helps stakeholders understand an entity's financial health by translating raw transactional data into standardized reports. The discipline serves many different audiences and operates under several specialized branches.

The primary branches of accounting address different information needs. Financial accounting focuses on external reporting for parties outside the organization, while managerial accounting provides internal reports that guide planning and operational decisions. Tax accounting ensures compliance with tax laws, and auditing independently verifies that financial statements have been prepared faithfully.

To make financial reporting comparable across businesses, accountants follow standardized frameworks. In the United States, Generally Accepted Accounting Principles (GAAP) provide detailed, rules-based guidance, while International Financial Reporting Standards (IFRS) offer a principles-based framework adopted by most other countries. The primary users of these statements include investors, creditors, regulators, management, and employees, all of whom rely on the reports to assess profitability, liquidity, solvency, and operational efficiency.

At the heart of every accounting system lies the fundamental equation, Assets = Liabilities + Owner's Equity. This equation expresses the basic truth that every resource a business controls (an asset) is financed either by creditors (a liability) or by owners (equity). Every transaction a company records must keep this equation in balance.

Assets are resources owned or controlled by a business that provide future economic benefits. They are split into current assets, expected to be converted to cash or used within one year (such as cash, accounts receivable, and inventory), and non-current assets held for longer periods (such as property, plant, and equipment). Liabilities are the opposite side: obligations arising from past transactions that represent claims by creditors. Current liabilities, like accounts payable, are due within a year, while long-term liabilities, such as bonds payable, extend beyond.

Owner's equity represents the residual interest in assets after deducting liabilities, including owner investments, retained earnings, and accumulated profits. To organize how these balances change, accountants also track two temporary flows. Revenue is income earned from normal operations such as sales of goods or services, while expenses are costs incurred to generate that revenue, including salaries, rent, and utilities. Together, revenues and expenses flow into the calculation of net income, which in turn affects equity. A chart of accounts is the structured list of every account a business uses, organizing them into the categories of assets, liabilities, equity, revenues, and expenses.

Every accounting system uses double-entry bookkeeping, recording each transaction with equal debits and credits so that the accounting equation always stays in balance. A debit is an entry on the left side of an account, increasing assets, expenses, and dividends while decreasing liabilities, equity, and revenue. A credit, on the right side, does the opposite. Every debit is matched by an equal credit in the same transaction. T-accounts are visual tools shaped like the letter T that help illustrate these effects, with debits on the left and credits on the right. Some entries involve more than two accounts; these compound journal entries still maintain equal debits and credits, and contra-asset accounts such as accumulated depreciation and the allowance for doubtful accounts carry balances opposite to their related assets.

The journey from transaction to financial statement follows a predictable accounting cycle. It begins in the journal, the book of original entry where transactions are recorded chronologically with debits and credits. From there, entries are posted to the general ledger, the complete record of all accounts and their balances. A trial balance is then prepared, listing all ledger accounts and their debit or credit balances; if total debits equal total credits, the books are arithmetically in balance.

At the end of each accounting period, accountants prepare adjusting entries to record accruals and deferrals, ensuring revenues and expenses fall into the correct period under accrual accounting. Once adjusted, a new trial balance is produced. Closing entries then transfer the balances of temporary accounts (revenues, expenses, and dividends) into retained earnings, leaving permanent accounts (assets, liabilities, and equity) to carry forward. A post-closing trial balance confirms that only permanent accounts remain and that debits still equal credits at the start of the new period. Many accountants use an accounting worksheet, a multi-column tool that combines trial balances, adjustments, and statement columns to organize this work. Outside the cycle, a bank reconciliation compares the company's cash records with the bank's statement to identify timing differences, errors, or possible theft.

Financial reporting rests on a set of foundational principles and assumptions. The going concern assumption presumes that a business will continue operating indefinitely, which justifies capitalizing assets over their useful lives. The economic entity assumption treats the business as separate from its owners and other entities, while the monetary unit assumption records transactions in a stable currency and ignores inflation. The time period assumption divides the life of the business into artificial periods such as quarters or years so that periodic financial statements can be produced. A fiscal year is any 12-month accounting period, which may end on a date other than December 31.

Several principles shape how transactions are recognized and reported. The cost (or historical cost) principle requires assets to be recorded at the cash or cash-equivalent amount paid at acquisition, providing objective and verifiable amounts. The matching principle requires expenses to be recorded in the same period as the revenues they helped generate, ensuring accurate measurement of profitability. The revenue recognition principle states that revenue is recorded when it is earned and realizable, not necessarily when cash is received, often requiring persuasive evidence of an arrangement and delivery. The conservatism principle advises understating assets or income and overstating liabilities when uncertainty exists, while materiality determines whether an item's size is significant enough to influence decisions. The full disclosure principle requires all relevant information affecting decisions to appear in the financial statements or accompanying notes.

These principles guide the construction of the four core financial statements. The balance sheet presents assets, liabilities, and equity at a specific point in time, reflecting the accounting equation in detail. The income statement reports revenues, expenses, and net income over a period, following the relationship Net Income = Revenues - Expenses. The statement of retained earnings shows how the retained earnings balance changed, beginning with the prior balance, adding net income, and subtracting dividends; this statement links the income statement to the balance sheet. The cash flow statement summarizes cash inflows and outflows from operating, investing, and financing activities, explaining changes in the cash balance over a period. Underlying the statements is a choice of timing basis: accrual accounting records revenues when earned and expenses when incurred, while cash basis accounting records them only when cash changes hands. Accrual accounting provides a more accurate picture of performance, but cash basis is simpler and common in small businesses.

Assets are the building blocks of the balance sheet, but their costs are usually allocated over time. When a cost will provide a future benefit lasting more than one period, accountants capitalize it as an asset on the balance sheet and then expense it gradually. A cost that is consumed immediately is expensed on the income statement. Fixed assets, also called property, plant, and equipment, are long-term tangible assets used in operations, such as buildings, machinery, vehicles, and land improvements; land is not depreciated because it does not wear out. Intangible assets, including patents, trademarks, copyrights, goodwill, and software, are long-term non-physical resources with future economic value; some are amortized over finite lives, while goodwill and many trademarks are considered indefinite-lived and tested annually for impairment, which is a write-down applied when an asset's fair value falls below its book value and the decline is other-than-temporary.

Depreciation is the systematic allocation of a tangible asset's cost over its useful life, matching the cost to the periods that benefit from it. Straight-line depreciation expenses an equal amount each year, computed as (Cost - Salvage Value) / Useful Life. Salvage value is the amount expected to be recovered when the asset is eventually disposed of. Units-of-production depreciation ties expense to actual usage, multiplying (Cost - Salvage) by the ratio of units used this period to total estimated units; this method suits machinery whose wear is closely linked to output. Double-declining-balance is an accelerated method that applies twice the straight-line rate to the asset's beginning book value, ignoring salvage until the book value approaches it. The depreciation expense reported on the income statement in any single period differs from accumulated depreciation, the running total of all depreciation recorded to date, which appears as a contra-asset on the balance sheet. The asset's net book value equals its original cost minus accumulated depreciation. When an asset is sold for more than its book value, depreciation recapture under U.S. tax law taxes part of the gain as ordinary income.

Inventory, a major asset for retailers, manufacturers, and wholesalers, is governed by several cost-flow assumptions. The First-In, First-Out (FIFO) method assumes the oldest costs are sold first, leaving the most recent costs in ending inventory; during inflation, this raises reported inventory and net income. The Last-In, First-Out (LIFO) method assumes the newest costs are sold first, matching current costs against current revenue and reducing taxable income in inflationary periods; LIFO is permitted under GAAP but prohibited under IFRS. The weighted-average method smooths price fluctuations by assigning the same unit cost to all items, recalculated each period. Specific identification tracks the actual cost of each item and is reserved for unique, high-value goods. LIFO liquidation occurs when a company sells more than it buys, dipping into older, cheaper layers and often raising reported income during inflation, and the LIFO reserve discloses the cumulative difference between LIFO and FIFO inventory to aid comparability. To prevent overstatement, the lower of cost or net realizable value (LCNRV) rule requires inventory to be reported at the lower of its historical cost or its selling price less completion and selling costs. Inventory flows into the income statement through cost of goods sold (COGS), calculated as Beginning Inventory + Purchases - Ending Inventory. Inventories may be tracked using a perpetual system, which updates records with every purchase and sale, or a periodic system, which updates only at period end through a physical count.

Financial statements become truly useful when their numbers are compared and interpreted through ratios. Liquidity ratios measure a company's ability to meet short-term obligations. The current ratio, calculated as Current Assets / Current Liabilities, indicates general short-term solvency, with values above 2:1 often considered healthy. The quick ratio excludes inventory and prepaid expenses, focusing on cash, marketable securities, and receivables divided by current liabilities; a value above 1.0 is generally sound. The cash ratio is the most conservative, dividing cash and cash equivalents by current liabilities. The operating cash flow ratio goes one step further, dividing cash flow from operations by current liabilities to test the ability to pay short-term obligations from actual cash generated.

Solvency and leverage ratios assess longer-term financial structure. The debt-to-equity ratio compares total liabilities to owner's equity, with higher values indicating more leverage and risk. Working capital, defined as Current Assets minus Current Liabilities, offers a simple dollar measure of short-term liquidity. The interest coverage ratio, Operating Income divided by Interest Expense, indicates the ability to service debt, with values below 1.5 signaling potential solvency problems. To gauge efficiency, analysts use the cash conversion cycle, which combines days inventory outstanding (DIO), days sales outstanding (DSO), and days payable outstanding (DPO); a shorter cycle frees up working capital and improves liquidity.

Profitability ratios show how well a company converts activity into earnings. Gross profit margin equals gross profit divided by revenue and measures profitability from core operations before overhead. Operating income subtracts selling, general, and administrative expenses from gross profit, while net income is the bottom line after interest and taxes; earnings per share (EPS) divides net income attributable to common shareholders by weighted-average shares outstanding. EBITDA, computed as Operating Income plus Depreciation and Amortization, is often used as a proxy for cash flow, especially for capital-intensive firms. Return on equity (Net Income / Average Equity) measures profitability for owners, return on assets (Net Income / Average Total Assets) measures how efficiently assets produce profit, and the net profit margin expresses net income as a percentage of revenue. The price-to-earnings (P/E) ratio shows how much investors pay for each dollar of current earnings, while book value per share divides total stockholders' equity by shares outstanding. Horizontal analysis compares financial statement line items across multiple periods as percentage changes, and vertical analysis expresses each item as a percentage of a base figure such as revenue or total assets.

Managerial accounting serves internal decision-makers with non-GAAP tools. The contribution margin is sales minus variable expenses, showing the amount available to cover fixed costs and contribute to profit; per-unit contribution margin guides pricing and product-mix decisions. The break-even point, calculated as Fixed Costs divided by Contribution Margin per Unit, is the sales volume at which total revenue equals total costs. The margin of safety measures how far actual or budgeted sales can fall before a loss occurs. Variable costing expenses only variable production costs as inventory costs and treats fixed manufacturing overhead as a period expense, while absorption costing (required by GAAP for external reporting) capitalizes fixed overhead into inventory until sold. A flexible budget adjusts the original plan to the actual level of activity, separating fixed and variable costs to allow fair performance evaluation, and variance analysis breaks differences between actual and budgeted results into price, volume, and efficiency components. Activity-based costing assigns overhead based on the activities products consume, giving more accurate cost information than simple volume-based allocation, while the economic order quantity formula \(\sqrt{2DS/H}\) identifies the order size that minimizes total inventory costs. Prime costs combine direct materials and direct labor, while conversion costs combine direct labor with manufacturing overhead.

Tax and long-term liability accounting introduce further complexity. A deferred tax asset arises when taxable income currently exceeds book income, representing future tax savings, while a deferred tax liability arises when book income exceeds taxable income; both stem from temporary differences that will reverse in future periods. The effective tax rate (Income Tax Expense / Pre-Tax Income) often differs from the statutory rate due to permanent differences and credits. FICA taxes fund U.S. Social Security and Medicare through both OASDI and Medicare components. Bonds, long-term debt securities, may be issued at a discount or premium depending on whether the stated rate is below or above the market rate, with the effective interest method amortizing that difference to interest expense over the bond's life. A contingent liability, such as pending litigation or product warranties, is recorded only if the loss is probable and reasonably estimable; otherwise, it is disclosed. A constructive obligation, created by past practice or published policies, is recognized even without a legal contract.

Several other specialized topics complete the picture. The accounting for receivables distinguishes the allowance method, which estimates uncollectible amounts in advance using tools such as the aging of receivables to assign higher bad-debt probabilities to older balances, from the direct write-off method, which recognizes bad debts only when specific accounts prove uncollectible. Long-term contracts may use percentage-of-completion revenue recognition, recognizing profit as work progresses, or the completed-contract method, which defers recognition until the project finishes. The equity method records an investor's proportional share of an investee's net income for significant influence, while consolidation combines a parent and its majority-owned subsidiaries into a single set of statements, eliminating intercompany activity and disclosing non-controlling interests separately. Capital structure distinguishes common stock, with voting rights and residual dividend claims, from preferred stock, which typically has dividend priority but no voting rights. Treasury stock, repurchased by the company, is a contra-equity account at cost, and additional paid-in capital reflects amounts investors paid above par value. Retained earnings follow the formula Ending = Beginning + Net Income - Dividends; cash dividends reduce assets, while stock dividends transfer value from retained earnings to contributed capital without changing total equity, and stock splits adjust share count and per-share price without affecting market value. Other comprehensive income records items like unrealized gains on available-for-sale securities and foreign currency translation that bypass the income statement. A change in accounting estimate, such as revising an asset's useful life, is applied prospectively. Discontinued operations are reported separately, net of tax, below income from continuing operations, and related-party transactions require disclosure because arm's-length terms may not apply.

Regulation, governance, and standards-setting shape the entire framework. In the United States, the Financial Accounting Standards Board (FASB) sets GAAP, issuing updates through the Accounting Standards Codification, while the Securities and Exchange Commission (SEC) oversees securities markets and requires public filings such as the 10-K, 10-Q, and 8-K. ASC 606 establishes a five-step model for revenue recognition: identify the contract, identify performance obligations, determine the transaction price, allocate the price, and recognize revenue when obligations are satisfied. The Sarbanes-Oxley Act of 2002 strengthened corporate governance, requiring CEO and CFO certification of financial statements and auditor attestation to internal controls. Internal controls, structured under the COSO framework, ensure reliable reporting and compliance, with segregation of duties a key safeguard. Auditors express opinions ranging from unqualified (clean) to qualified, adverse, or disclaimer, depending on the materiality and pervasiveness of any misstatements. Fair value, the price that would be received in an orderly market transaction, underlies mark-to-market accounting used for trading securities and derivatives, and IFRS also allows fixed assets to be revalued to fair value, a treatment GAAP generally does not permit. IFRS and GAAP differ in several respects: IFRS prohibits LIFO, requires inventory at the lower of cost and net realizable value, and allows capitalization of development costs once feasibility is established, whereas GAAP requires most research and development to be expensed as incurred. A tax shield refers to deductions such as depreciation and interest expense that reduce taxable income, with its value equal to the tax rate times the deductible amount.