What is the difference between straight groove thread milling cutter and spiral thread milling cutter in application?

It is generally believed that the straight groove and the spiral groove have different ways of discharging chips, the former discharging chips downwards and the latter discharging chips upwards. The spiral groove also has anti-seismic function. Because it is always in contact with the cutting surface with the same number of teeth. There will be gaps in the straight groove. Because the straight groove is not as deep as the spiral groove, the tool strength is stronger than the spiral groove.