doc updates

assets/version-aligner.css

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+/* Fix font size inconsistency in API endpoint descriptions */
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fundamentals/data-import-and-migration.mdx

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+---
+title: "Data Import and Migration"
+sidebarTitle: "Data Import and Migration"
+---
+
+Data import and migration enables you to transfer existing chat data from your own servers or another chat provider to CometChat. This ensures continuity of service and preserves your users' conversation history during the transition.
+
+## What Can Be Migrated?
+
+CometChat's migration capabilities cover:
+
+- **Users**: User profiles, metadata, and account information
+- **Messages**: Complete message history including text, media, and metadata
+- **Groups**: Group configurations and membership information
+- **Conversations**: Conversation threads and their associated data
+
+## Migration Approaches
+
+CometChat offers two approaches to data migration, depending on your needs:
+
+### Historical Data Import
+
+Import all your existing data at rest—stored messages, users, and groups—into CometChat before going live. This approach is ideal when:
+
+- You're doing a complete platform switch
+- You want all historical data available from day one
+- Your migration can happen during a maintenance window
+
+The Data Import APIs handle bulk ingestion of historical chat data, allowing you to transfer large volumes of users, messages, and group information efficiently.
+
+### Live Data Migration
+
+Maintain communication between users on your old system and users who have already migrated to CometChat. This approach is ideal when:
+
+- You need zero downtime during migration
+- Users will upgrade to the new app version gradually
+- Seamless communication must continue throughout the transition period
+
+Live migration bridges both systems during the upgrade cycle, ensuring no messages are lost regardless of which system a user is currently on.
+
+## Getting Started
+
+**For Historical Data Import**: Use the [Data Import REST APIs](/rest-api/data-import) to programmatically import your users, messages, and groups.
+
+**For Live Data Migration**: [Contact our Sales team](https://www.cometchat.com/contact-sales) to discuss your migration requirements and set up the live migration process.