Compressing files

1. Lossless

1.1. Lossless compression is a class of data compression algorithms that allows the original data to be perfectly reconstructed from the compressed data.

2. The compression algorithm

2.1. is a procedure the computer does to encode the original file

2.2. Computer scientists research these algorithms and come up with better ones that can work faster or make the input file smaller.

2.3. Two types of compression algorithms are Lossless and lossy

3. Compressing

3.1. Making the files smaller by removing redundant information

3.2. The former is still referred to as archiving, while the latter is just called compression

4. Lossy

4.1. Lossy compression often benefits media because it results in smaller file sizes and people can’t tell the difference between the original and the version with the changed data.

5. Archiving

5.1. Combining multiple files into one.

6. File archiving

6.1. Used when one or more files need to be transmitted or stored:

7. Values

7.1. Make a large number of files available

7.1.1. Download a compressed archive than it is to download individual files

7.2. Log files with habit of filling disks

7.2.1. It is helpful to split them by date and compress older versions

7.3. To back up directories

7.3.1. Easier to keep in one archive

7.4. Streaming devices perform better

7.4.1. Sending a stream of data rather than individual files

7.5. Faster to compress a file before sending than sending it uncompressed

8. Tools

8.1. gzip –d

8.1.1. does same the

8.1.1.1. gunzip

8.2. Commands

8.2.1. -1

8.2.2. mysqldump –A

8.2.3. > database_backup.gz

8.2.4. gzip –l

8.2.5. bzip2

8.2.5.1. bunzip2