'signal words' are words in a sentence that show which direction an idea is moving. 'logical connectors' are words that join together ideas in, or parts of, a sentence in order to improve clarity.

cause and effect = one thing "a cause" creates an outcome - the effect. History teaches us many causes and effects. The results of the Treaty of Versailles after WWI, taking away much land from Germany, was the underlying cause for WWII.