TestDisk is a free and open-source data recovery software that can recover lost or deleted data from hard drives and storage devices. This program supports various file systems, including NTFS, FAT32, and ext2/ext3/ext4. It also has a command-line interface, which makes it a popular choice among experienced users.
One of the best features of TestDisk is its ability to repair damaged partition tables and recover lost partitions. It's also designed to be an easy-to-use tool that can help inexperienced users recover lost data.