tar xzvf <filename> -> "tar eXtract Zipped Verbose File <filename>"

tar czvf <filename> <files> -> "tar Compress Zipped Verbose File <filename> <files>"

So it's either x or c if you want to unzip a tar file or create one

Add z if the thing you're uncompressing ends in .gz, or if you want the thing you're creating to be compressed.

v is just if you want the filenames to be printed to stdout as they're extracted or imported

f tells it to read from or output to a file, as opposed to reading from stdin or output to stdout

Then your provide the filename to read from/export to, and if you're exporting you then provide the file list.

Not that hard.