In the past the hair styling depends on some traditional tools.
But now the styling depends a lot of technology, techniques and essential tools of the most important for example blow-dryer and flat iron.
Temperature VS Hair styling.
High temperature resulting from a hair dryer and flat iron is very essential for hair styling and straightening because of the high temperature is break some simple bonds into the hair (Hydrogen bonds) to straight your hair according to your style.
Safety of Blow-dryer and flat iron.
High temperature can damage your hair, leading to dryness and split ends. If you use it frequently or use these tools form unknown brands or forget use hair protection spray before use flat iron.