what is the best software or program that has file version control system with backup and virtualization capabilities that can be run locally and is free of cost, preferably open source

There are several open-source tools that provide file version control, backup, and virtualization capabilities that can be run locally. Here are some of the best options you might consider: ### 1. **Git** - **Overview**: Git is a widely-used distributed version control system that allows you to track changes in your files. - **Backup**: You can push your repositories to remote servers like GitHub, GitLab, or Bitbucket for backup. - **Virtualization**: While Git itself doesn't offer virtualization, you can use Docker (see below) alongside Git to manage virtualized environments. - **Cost**: Free and open source. ### 2. **Docker** - **Overview**: Docker is a platform that allows you to develop, ship, and run applications in containers. - **Version Control**: Docker images can be versioned and managed in a way similar to version control. - **Backup**: You can create snapshots of containers and manage your data with volumes that can also be backed up. - **Cost**: Free and open source. ### 3. **BackupPC** - **Overview**: BackupPC is a high-performance, enterprise-grade system for backing up PCs and laptops. - **Version Control**: It provides backup retention policies that can serve to keep versioned copies of backups. - **Cost**: Free and open source. ### 4. **BorgBackup (Borg)** - **Overview**: BorgBackup is a deduplicating backup program that supports compression and encryption. - **Version Control**: It allows for versioning through its backup snapshots. - **Cost**: Free and open source. ### 5. **Restic** - **Overview**: Restic is another backup program that is fast, secure, and efficient. - **Version Control**: It uses a snapshot mechanism that can give you access to previous versions of your files. - **Cost**: Free and open source. ### 6. **Duplicati** - **Overview**: Duplicati is a backup solution that supports various backends for storing backups. - **Version Control**: It allows for incremental backups, which provide versioning capabilities. - **Cost**: Free and open source. ### 7. **FreeFileSync** - **Overview**: FreeFileSync is a folder comparison and synchronization software. - **Backup**: While it is not a backup tool per se, you can configure it to synchronize folders for backup purposes. - **Version Control**: It does not provide full version control but can help manage fold changes. - **Cost**: Free and open source. ### Considerations: While mixing tools can offer broader functionalities, you might need to integrate them effectively to achieve a workflow that meets all your needs. For example, you might use Git for version control of your project files, combined with BorgBackup or Restic for backups, and Docker for virtualization. Make sure to evaluate your specific use case to find the best combination of these tools.