the data from these two files using employee-id as shown below.
$ cat employee.txt
100
200
300
400
Jason Smith
John Doe
Sanjay Gupta
Ashok Sharma
$ cat bonus.txt
100
200
300
400
$5,000
$500
$3,000
$1,250
$ join employee.txt bonus.txt
100
200
300
400
Jason Smith $5,000
John Doe $500
Sanjay Gupta $3,000
Ashok Sharma $1,250