Server side code                      Client Side

1. Use scriting language      1.USed language VBscript or 
ASP or JSP(Java Server pages)   JavaScript

2. Use runat="server" in code. 2. It doesnt use it.

Mr.Dan you are not utterly, right letme explain what are 
those things man

server side:
This is code/routines executed only on the server. Code can 
be written in scripts as well (vbscript usually), but in 
the case of ASP.Net this is the compiled lanuages like C# / 
VB.Net. Used for processing content and returning data.

Client side:

This is code/routines that are not processed at all by the 
server. Code is written in scripts (javascript usually) - 
plain text commands that instruct the client to do 
something. Generally used for performing dynamic effects, 
such as image rollovers, or displaying message boxes, or 
even validation of data entered into a form (i.e. email 
address is in the format of an email address ... contains 
the @ symbol).

server-side excute the code in server side
client-side excute the code in browser side