An explosive booster is a sensitive explosive charge that acts as a bridge between a (relatively weak) conventional detonator and a low-sensitivity (but typically high-energy) explosive such as TNT. By itself, the initiating detonator would not deliver sufficient energy to set off the low-sensitivity charge. However, it detonates the primary charge (the booster), which then delivers an explosive shockwave that is sufficient to detonate the secondary, main, high-energy charge.
Unlike C4 plastic explosive, not all explosives can be detonated simply by inserting a detonator and firing it.
An initiator such as a shock tube, cannon fuse, or even a conventional detonator does not deliver sufficient shock to detonate charges comprising TNT, Composition B, ANFO and many other high explosives. Therefore, some form of "booster" is required to amplify the energy released by the detonator so that the main charge will detonate.
Tetryl was once a very popular chemical for booster charges, particularly during World War II, but has been largely superseded by other compositions, e.g. a small cylinder or pellet of phlegmatized RDX or PETN (slightly larger than the actual detonator) into which the detonator itself is inserted.
(Album: The Game, 1980)
"Yeah
Hey hey hey
No I'll never look back in anger
No I'll never find me an answer
You promised me, you'd keep in touch
I read your letter and it hurt me so much
I said I'd never, never be angry with you
I don't wanna feel like a stranger (no)
'Cos I'd rather stay out of danger
I read your letter so many times
I got your meaning between the lines
I said I'd never, never be angry with you
I must be strong so she won't know how much I miss her
I only hope as time goes on I'll forget her
My body's aching, can't sleep at night
I'm too exhausted to start a fight
And if I see her with another guy
I'll eat my heart out 'cos I love, love, love, love her
Come on baby, let's get together
I'll love you baby, I'll love you forever
I'm trying hard to stay away
What made you change, what did I say ?
Ooh I need your loving tonight
Ooh I need your loving
Ooh I need your loving
Ooh I need your loving babe tonight (Hit me)
Ooh I need your loving tonight
No I'll never look back in anger
No I'll never find me an answer
Gave me no warning, how could I guess
I'll have to learn to forgive and forget
Ooh I need your loving
Ooh I need your loving