Solid Archives

A solid archive is one where all of the stored files are compressed in a single operation.

Advantages...
  - Much better compression is achieved.

Disadvantages...
  - Slower access, the whole archive must be decompressed in order to retrieve a singe file.
  - A single error will make all the files in the archive unrecoverable.

Notes:

1. Tar files are not compressed so saving them as a tar.gzip or tar.bzip2 will create a solid archive.

2. A zip file is typically not a solid file because the files are compressed individually, however setting the zip compression level to '0' and then saving the archive as a zip.gzip or zip.bzip2 will create a solid archive.

3. The "force zero compression for solid archives" option in the preferences dialog will automatically set the zip compression level to zero when saving as zip.gzip or zipl.bzip2 (or any other recognised equivalent extension).