This is an example of the Yamaha DX7 in use on Queen's 'One Vision' track. 

In the 80's Yamaha first produced a FM synthesiser. This was called Yamaha DX7. FM Synthesis worked by using additive synthesis, which combines sine waves together rather than starting from scratch and then creating a sound from there, like in subtractive synthesis. FM synthesis was good for reproducing and imitating sounds like electric pianos or brass. But due to its  hard and metallic sounds it wasn't great to imitate the richer sounds that are produced on string instruments. 

Low frequency oscillators give out a frequency in the same way as oscillators  do. The difference between the two is that the basic oscillators  produces an audible frequency where as an LFO gives out a signal with a relatively low frequency that is inaudible to the human ear. 

LFO waveforms can depend entirely upon the synthesiser, but they commonly employ sine, saw, triangle, square and hold waveforms. 

In other posts i have described and explained the difference between these waveforms and also uploaded some examples of what you can use these waveforms for. 

The different shapes depend on how quickly they rise and fall. The LFO can be great when trying to create a wobble bass sound or anything to do with dubstep. 

The LFO has its own envelope too, which means you can control where the decay, sustain, attack and release happen to the sound. The attack and release is how hard or quiet the sound comes in and leaves. The sustain is how long the sound will be played until the release/fade kicks in and the decay is the same as the fade. 

Subtractive synthesis is the very basic of many forms of synthesis and is usually relative to analogue synthesisers. It happens by combining a number of 'oscillators' to create a timbre that is very rich in its harmonics. This sound can then become sculptured using a set of 'modifiers'. The number of modifiers on a synth is entirely dependant on the model, but all of them offer a way of filtering out certain harmonics and of shaping the overall volume of the timbre. 

Subtractive synthesis in logic is the ES2. It is very simple to use and impressive seeing as how much it does. 

Next is an analogue synthesiser. Any synthesiser that emulates analogue synthesis will operate essentially the same way. The only difference between other synthesisers is that the original synthesiser voltages do not apply to their DSP equivalents. 

 An analogue synth has three components :

An oscillator to make the initial sounds.

A filter, to filter the sound.