IRS Publication 583: Starting a Business and Keeping Records
Internal Revenue Service
United States federal guidance on what records a business must keep and for how long, choosing an accounting method, and single versus double entry, with a worked example of a shop's daily receipts, monthly summaries and check disbursements. US-specific.
More resources on Bookkeeping & Small Business Accounting
Lecture 18: Legal and Accounting Basics for Startups
Stanford CS183B lecture in which Y Combinator's CFO Kirsty Nathoo and general counsel Carolynn Levy cover incorporating as a Delaware C corporation, founder equity and vesting, 83(b) elections, fundraising paperwork, bookkeeping, and cash management. Founders can avoid common early legal and accounting mistakes.
GnuCash Tutorial and Concepts Guide
Official manual for the open-source double-entry accounting program, teaching concepts alongside the software: chart of accounts setup, transactions, reconciliation, then business features including customer invoices, vendor bills, receivables, payables, sales tax tables and a payroll example.
Accounting Stuff (YouTube channel)
Short animated videos on the accounting equation, debits and credits, journal entries, ledgers and the accounting cycle. The Accounting Basics series functions as a sequenced beginner course before any software is introduced.
AccountingCoach: Bookkeeping Explanation
A free multi-part written explanation of bookkeeping covering cash versus accrual, debits and credits, the general ledger and chart of accounts, bank reconciliation, adjusting and reversing entries, and the three financial statements, with practice quizzes.