Nick has a Samsung TV and he wants to cast videos from his computer or tablet. Leo says that most TVs support DNLA, which would enable him to stream to the TV. Samsung calls it "Samsung Link" or "All Share." He should Google the TV model and "DLNA" or "Miracast" and he will find out how he can do it. It may also be called "screen mirroring."
Most Windows devices and tablets will support DLNA. The Samsung Galaxy Note would be a good tablet choice, as are the Galaxy Tabs. Leo likes the Galaxy Tab S2. Any Bluetooth keyboard will work also, and the TV will support it.