zstd:tldr:b1b42

The command "zstd ${filename}" is used to compress a file using the zstandard compression algorithm.

Here's a breakdown of each element in the command:

• "zstd": This is the command-line utility used for compressing or decompressing files with the zstandard compression algorithm.
• "${filename}": This is a placeholder for the actual filename you want to compress. You need to replace "${filename}" with the name of the file you want to compress, including its extension.

For example, if you want to compress a file named "file.txt" using zstd, you would replace "${filename}" in the command with "file.txt" like this:

zstd file.txt

After executing this command, zstd will compress the "file.txt" file and create a compressed output file with the ".zst" extension (e.g., "file.txt.zst" if you are using the default options).