> For the complete documentation index, see [llms.txt](https://docs.lightning.engineering/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.lightning.engineering/the-lightning-network/payment-lifecycle.md).

# Lightning Network Invoices

The Lightning Network uses a system of invoices instead of addresses, reflecting the network’s primary function of a payment network. Invoices are generated by the recipient of a payment, and the validity can be limited to a certain amount of time.

Each invoice is signed by the recipient and contains an amount, expiration time, destination pubkey, supported features and others. Invoices can be canceled by the recipient, too.

These mechanisms help eliminate overpayments, underpayments, late payments and duplicate payments and can be configured to handle tips and partial payments.

{% content-ref url="/pages/-MduvSuG8D5K6jFz7Vnb" %}
[Understanding Lightning Invoices](/the-lightning-network/payment-lifecycle/understanding-lightning-invoices.md)
{% endcontent-ref %}


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