Explain the need of parameters in Loadrunner?

The functionality of parameters are same every where ( whether in loadrunner, c, java etc..). Parameters act as a variable in the code, and they help in passing different values to the servers every time when it talks to the server. i.e we wat to run the load test on “Login” functionality with 5 users simultaneously. So, we record the script first time by logging into the application by using a user id / pwd. To conduct load test with 5 users, we need 5 sets of user ids/pwds to simulate 5 different users logging at the same time. In this situation, we create parameters with two variables ex ‘username’ & ‘password’, and we pass 5 sets of userids/pwds to the script so that the parameters will replace with a new value every time when the script runs. Parameters will reduce the length of the code