Language: BASH.....

#Script showing username, date, user_id and current directory
echo "Hello, $LOGNAME"
echo "Current date is `date`"
echo "User is `who i am`"
echo "Current directory `pwd`"

#Script giving execution permission and executing
chmod 755 file.sh
./file.sh
#To find reverse of a number
# sh script.sh 3487
#!/bin/bash
if [ $# -ne 1 ]
then
    echo "Usage: $0   number"
    echo "       I will find reverse of given number"
    echo "       For eg. $0 0123, I will print 3210"
    exit 1
fi

n=$1
rev=0
sd=0

while [ $n -gt 0 ]
do
    sd=`expr $n % 10`
    rev=`expr $rev \* 10  + $sd`
    n=`expr $n / 10`
done
    echo  "Reverse number is $rev"

#Pipe the calculated value to bc command
echo 7.56 + 2.453 | bc

# Show value of pi up to 15 digits  (for it pi package must be installed)
pi 15