Hi,
Can anyone let me explain the difference between tar , uncompress,gzip and gunzip commands.
both gzip and gunzip are same i think correct me if am wrong.
tar - Tape ARchiver. Originally intended to write/read files to/from a tape device. Does not support compression
compress/uncompress - Uses LZC compression, can handle only single files, used together with tar to create compressed archives (what Windows-users would call "zipping")
gzip/gunzip - Uses the DEFLATE algorithm, otherwise behaves like compress
bzip2/bunzip2 - Uses a lossless compression algorithm, otherwise behaves like compress
The reason that gzip and gunzip seem to be the same is because they are the same. On most systems there's only a gzip executable, with gunzip being a link to that. What to do by default (compressing/decompressing) is decided by the name it was executed as. Same for bzip2/bunzip2. You can check this by running
$ ls -l `which gzip`
$ ls -l `which gunzip`