# bc > An arbitrary precision calculator language. > See also: `dc`, `qalc`. > More information: . - Start an interactive session: `bc` - Start an interactive session with the standard math library enabled: `bc {{[-i|--interactive]}} {{[-l|--mathlib]}}` - Calculate an expression: `echo '{{5 / 3}}' | bc` - Execute a script: `bc {{path/to/script.bc}}` - Calculate an expression with the specified scale: `echo 'scale = {{10}}; {{5 / 3}}' | bc` - Calculate a sine/cosine/arctangent/natural logarithm/exponential function using `mathlib`: `echo '{{s|c|a|l|e}}({{1}})' | bc {{[-l|--mathlib]}}` - Execute an inline factorial script: `echo "define factorial(n) { if (n <= 1) return 1; return n*factorial(n-1); }; factorial({{10}})" | bc`