: Adding or deleting files in a solid archive usually requires the entire archive to be rewritten, which can be time-consuming for large files like a "W-4111.7z" package. Why is it used for W-4111.7z?

: To extract a single file from the middle of a solid archive, the software must decode all preceding data in that "solid block." This can make extracting individual files slower than in standard ZIP files.

: It significantly reduces file size compared to non-solid archives, especially for collections of small, similar files.

When a 7z archive is created as a "solid" archive, the compression algorithm treats all files within the archive as one continuous data stream. This is highly effective when the archive contains many similar files (such as different versions of the same document or multiple text files), as the compressor can identify and eliminate redundancies across file boundaries. Key Characteristics

In the context of the compressed archive , the "solid" feature refers to Solid Compression , a specific method used by the 7-Zip (7z) format to improve the compression ratio. What is Solid Compression?