Convert string to hexadecimal on command line

echo -n "Hello" | od -A n -t x1

Explanation:

• The echo program will provide the string to the next command.
• The -n flag tells echo to not generate a new line at the end of the “Hello”.
• The od program is the “octal dump” program. (We will be providing a flag to tell it to dump it in hexadecimal instead of octal.)
• The -A n flag is short for --address-radix=n, with n being short for “none”. Without this part, the command would output an ugly numerical address prefix on the left side. This is useful for large dumps, but for a short string it is unnecessary.
• The -t x1 flag is short for --format=x1, with the x being short for “hexadecimal” and the 1 meaning 1 byte.