Question

what does mean laplace transfourmation?

Answer 1

It basically used to solve initial-valued differential equations of the 2nd (or higher) order.
In respect of engineering, when we studies systems in tine domain we can analyse the system at t=0. But what about t=infinite. Does it exist practically. No
So what we do is we inverse the system or transform it to the s domain or frequency domain now you can study the system at s=0 which implies t=infinite. Is in it a good trick ? :-)