wireless - Connect to WiFi network through Ubuntu terminal

I am using my WiFi network adapter on the laptop to connect to the internet on Ubuntu 10.04.
I have tried the following steps and got the below messages on the Ubuntu terminal.
Please let me know what has gone wrong.
Thank you.

I have used the following instructions I have seen on a web page.

1. Open the terminal.




2. Type ifconfig wlan0 and press Enter. You will not see any output in the terminal, as this command just turns your wireless card on. Most wireless cards are designated wlan0. If yours has a different designation, use that instead.





3. Type iwconfig wlan0 essid name key password and press Enter. Replace name with the actual network name, and replace password with the actual security key for the network. If your wireless network does not require a security key, do not enter key password.




4. Type dhclient wlan0 and press Enter to obtain an IP address and connect to the WiFi network.

What I see on the terminal are given below.