So are all Chinese words made up of single characters?
No. Most words in Chinese are actually made up of a combination of characters. For example when you combine fire 火 and vehicle 车 you get 火车 – 'fire vehicle', or as we know it in English; train.
Similarly, if you combine electric 电 with vision 视 you get 'electric vision' 电视 – in English; television.
'Electric speech' is 电话 – telephone, 'electric brain' 电脑 – computer, and 'electric shadow' 电影 – film.