Encryption on Post Or get

Hello
how can I Secure My Scripts that Use login system . if a sniffer is in network then he can see my passwords so how can i encrypt or encode data transfer.is any function or algorithm to do this . like i want to encode pass word on client and send it to server and then decrypt it.

no . except this one. i want when a user click on submit button the script encode/encrypt his/her password and then send it to server .
what is client and server side scripts . (client using java script and server asp).i think this is more secure.

Now i'm not going to give this a Safest in the world security but you could always use a javascript oneway encryption function and then send the hashed password over the internet and then compare it on the server... that isn't the most seucre way but it would be better than nothing... what's better?

mypassword

or

LK4LK7J2LK4J74LK7J247JHG4O2I6G&25745852

I would not recommend any client side encryption, if this is for a login app you could use DIGEST authentication which is  a bit like BASIC authentication but an MD5 digest is sent instead of plain text.

The trouble with client side encryption is:

1) You will never get it as strong as SSL because you won't be able to handle key's etc.

2) Anybody can view your code and identify weaknesses via View Source