Can words really change the world? From the absurd to the inspirational, from the divine to the diabolical, these are the speeches that have changed history, and left their mark on the world today.

To read of Elizabeth I addressing her troops before the Spanish Armada, or Martin Luther King urging the American population to racial equality is to understand the tremendous power of language to inspire, to comfort, to move or to enthuse an audience.

It is inspiring to hear the words of people whose gift was to know what to say, when to say it, and how to phrase it, often in language so powerful, so eloquent and so beautiful that we remember their words centuries after they were first spoken.

I Have a Dream includes some of the greatest, most celebrated speeches, such as Pericles' funeral oration in Athens in the fifth century BC, as well as lesser-known speeches, such as Lieutenant-Colonel Tim Collins' eve-of-battle address to his soldiers in Iraq in 2003 - all of which deserve to be celebrated and credited by modern audiences.

Here is an enjoyable collection of the greatest speeches that have been delivered throughout history, prefaced by brief historical and biographical introductions.