QuickBooks Online is a cloud-based accounting platform developed by Intuit that enables small to midsize businesses to manage their complete financial operations through a web browser or mobile app. It automates core bookkeeping tasks—invoicing, expense tracking, bank reconciliation, payroll integration, and financial reporting—while providing real-time visibility into cash flow and business performance. Unlike desktop accounting software, QBO stores data on secure cloud servers, allowing multiple users, accountants, and business owners to collaborate from anywhere with automatic updates and backups. The platform operates on a subscription model with tiered plans (Simple Start, Essentials, Plus, Advanced) that scale with business complexity, offering progressively more features like multi-user access, project tracking, inventory management, and custom reporting. A key mental model: QuickBooks Online is your business's financial command center—every transaction flows through it (income, expenses, assets, liabilities), and its chart of accounts acts as the foundation that categorizes every dollar, enabling accurate reporting and tax compliance.