Brief description for some of the special variables are given below:

• $0 contains the input record content
• $1 first field
• $2 second field and so on
• FS input field separator
• OFS output field separator
• NF number of fields
• RS input record separator
• ORS output record separator
• NR number of records (i.e. line number) for entire input
• FNR number of records per file