Can I use both Wi-Fi and data plan on my iphone 4s t the same time?

I have activated my data plan and i'm also receiving Wi-Fi from home. When i turn the Wi-Fi on i can see the Wi-Fi bars. When i turn the Wi-Fi off i can see the E which means my data plan is on. I was wondering if i can turn my Wi-Fi on and also use my data plan at the same time on my iphone 4s?

Technically no. It uses one or the other, but you can leave the data on while using Wi-Fi so that if/when you no longer can access it it would automatically switch.