Like ticks, fleas are blood-sucking parasites that typically infest a larger creature, commonly a house pet. They are much smaller than ticks, and therefore less detectable; their mouth parts are very well adapted to piercing skin. They are small enough to travel through bed sheets and clothing, and they can hide in hair or fur, which is why so many cats and dogs become infested with the parasites. Unlike ticks, fleas are able to move around, and are legendary for their jumping ability. While they don't spread as many pathogens as ticks do, flea bites usually cause rashes and other unpleasant effects. Due to its size and mobility, the flea is the classic disreputable flop-house pest.
For DIY pest control for fleas, Partners Pest Control offers a great range of pesticides and other products.