: The .7z extension signifies that the data is compressed using the 7-Zip open-source format, known for high compression ratios using the LZMA and LZMA2 algorithms.

: If you don't have it, download the free utility from the official 7-Zip website.

: Right-click the .001 file and select 7-Zip > Extract Here . The software automatically recognizes the subsequent parts and merges them back into the original file.