Software synthesisers and samplers can be found in a huge variety of different types. Put simply, a software synthesiser is a software instrument that can produce and manipulate sound much like a hardware synthesiser might. A typical software sampler can play recordings of sounds and offer editing and layering features as well sound effects processors and sound synthesis tools. Software instruments are sometimes called virtual instruments.

Sometimes sequencing applications include software instruments so users have a range of sounds with which to get started. When deciding on a suitable software instruments beyond any you might initially get, however, you should look at the kinds of sounds and features that particular vitual instuments offer. It might be that you need an instrument that offers a broad library of sounds for general use - an instrument that is simple to use and can be set up easily. On the other hand you might need a specific kind of instrument associated with a particular style of music or with a type of sound in mind.

If you are not sure what would suit your needs it might be advisable to purchase an all-in-one software 'bundle' product that includes sequencer host applicaion and software instruments. At least in this way you will be able to get started and then add to your software instruments or sound libraries at a later time.