Effects can be the little treat to your track but also powerful tools to make your tracks working in a mix.
There are two categories of effects we look at:

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Those effects which change the level of a signal are dynamic effects:
- filter
- equalizer
- compressor / limiter
- combinations like deesser or
- multiband compressors

Effects which will add something to the signal are send- or delay effects
- delay
- reverb
- modulation effects like
- phaser
- flanger
- chorus

As addition to this there are special effect and sound synthesis modules available.