> For the complete documentation index, see [llms.txt](https://docs.opencart.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.opencart.com/admin-interface/system.md).

# System

- [Settings](https://docs.opencart.com/admin-interface/system/settings.md): Configuring store visual identity, theme, logo, and SEO meta tags in OpenCart 4
- [Store](https://docs.opencart.com/admin-interface/system/settings/store.md): Configuring store contact details and location information in OpenCart 4
- [Local](https://docs.opencart.com/admin-interface/system/settings/local.md): Configuring store localization, languages, and currencies in OpenCart 4
- [Option](https://docs.opencart.com/admin-interface/system/settings/option.md): Configuring core business logic, checkout options, and storefront behavior in OpenCart 4
- [Mail](https://docs.opencart.com/admin-interface/system/settings/mail.md): Configuring email protocols and notification alerts in OpenCart 4
- [Server](https://docs.opencart.com/admin-interface/system/settings/server.md): Configuring server-side technical options, security, and SEO in OpenCart 4
- [Localization](https://docs.opencart.com/admin-interface/system/localization.md): Managing regional settings, languages, currencies, taxes, and geographical data for multi-store and international operations
- [Languages](https://docs.opencart.com/admin-interface/system/localization/languages.md): Managing store languages, locale settings, and translation configurations for multilingual stores
- [Currencies](https://docs.opencart.com/admin-interface/system/localization/currencies.md): Managing currency configurations, exchange rates, and display formats for international stores
- [Stock Statuses](https://docs.opencart.com/admin-interface/system/localization/stock-statuses.md): Defining inventory availability messages displayed to customers when viewing products
- [Order Statuses](https://docs.opencart.com/admin-interface/system/localization/order-statuses.md): Defining order workflow stages and status labels for customer communication and internal tracking
- [Returns](https://docs.opencart.com/admin-interface/system/localization/returns.md): Configuring return statuses, actions, and reasons for handling product returns and refunds
- [Countries](https://docs.opencart.com/admin-interface/system/localization/countries.md): Managing country definitions, address formats, and postal code requirements for international operations
- [Zones](https://docs.opencart.com/admin-interface/system/localization/zones.md): Managing regional subdivisions (states, provinces, territories) within countries for address validation and regional rules
- [Geo Zones](https://docs.opencart.com/admin-interface/system/localization/geo-zones.md): Creating custom geographical groupings that combine countries and zones for shipping rules and tax calculations
- [Tax Classes](https://docs.opencart.com/admin-interface/system/localization/tax-classes.md): Creating tax categories that group multiple tax rates for different products and services
- [Tax Rates](https://docs.opencart.com/admin-interface/system/localization/tax-rates.md): Defining specific tax percentages or fixed amounts applied to products based on geographical zones and customer groups
- [Length Classes](https://docs.opencart.com/admin-interface/system/localization/length-classes.md): Defining measurement units for product dimensions (centimeters, inches, meters, etc.) with conversion rates
- [Weight Classes](https://docs.opencart.com/admin-interface/system/localization/weight-classes.md): Defining weight units for products (kilograms, pounds, ounces, grams, etc.) with conversion rates for shipping calculations
- [Address Formats](https://docs.opencart.com/admin-interface/system/localization/address-formats.md): Managing address format templates for consistent address display across countries and regions
- [Maintenance](https://docs.opencart.com/admin-interface/system/maintenance.md): Create, restore, and manage database backups to protect your store's data and ensure business continuity
- [Error Logs](https://docs.opencart.com/admin-interface/system/maintenance/error-logs.md): Monitor, analyze, and manage system error logs to identify issues, debug problems, and maintain store stability
- [Upgrade](https://docs.opencart.com/admin-interface/system/maintenance/upgrade.md): Check for, download, and install OpenCart updates to keep your store secure and up-to-date with the latest features
- [Uploads](https://docs.opencart.com/admin-interface/system/maintenance/uploads.md): Manage customer file uploads, track submission history, and handle file downloads for personalized orders and custom product requests
- [Users](https://docs.opencart.com/admin-interface/system/users.md)
- [User Groups](https://docs.opencart.com/admin-interface/system/users/user-groups.md): Defining permission sets and access controls for administrative roles in OpenCart 4
- [API](https://docs.opencart.com/admin-interface/system/users/api.md): Generating and managing API credentials for external integrations and secure data exchange