> ## Documentation Index > Fetch the complete documentation index at: https://docs.onboard.xyz/llms.txt > Use this file to discover all available pages before exploring further. # Introduction The Onboard Business account is a stablecoin-backed USD account. Money can enter or leave in any supported form — stablecoin or fiat — and is held in your account as USD. Stablecoins and fiat flow into and out of the Business Account, which holds funds as USD ## Primary account and sub-accounts Every business gets one **primary account**. Underneath it, you can create any number of **sub-accounts** — each with an independent balance, its own virtual account number, its own crypto deposit addresses, and its own activity feed. Sub-accounts are commonly used to represent your end customers or business units, while still settling through your one primary Onboard relationship. * [Primary account](/guides/product-features/virtual-account/primary-account) * [Sub-accounts](/guides/product-features/virtual-account/sub-accounts) * [Virtual account number](/guides/product-features/virtual-account/account-number) * [Webhooks for Virtual Accounts](/guides/product-features/virtual-account/webhooks)