Ignition temperature is the minimum temperature that a substance must be raised to before it will ignite. It is the temp at which the object or whatever is capable of burning. Eg - If there is no oxygen, the object will not burn even after reaching its ignition point.
Flashpoint is the minimum temperature at which liquid will give off vapours that will ignite. “They don’t have to remain ignited they will usually just flash.”
Burning temperature is the temperature at which a product will give off vapours sufficient to cause self-sustained combustion.