It's called an ant lol and it's an insect
Spotted tussock moth caterpillar
The distinguishing feature of a grey caterpillar with black spots is its unique coloration, which sets it apart from other caterpillar species.
The Rusty Tussock Moth or Vapourer, Orgyia antiqua
The black and yellow caterpillar with spikes is called a "cinnabar moth caterpillar."
The name of the yellow and black caterpillar with spikes is the "Eastern Tiger Swallowtail caterpillar."
This caterpillar is from the Gulf Fritillary (Agraulis vanillae), also known as the Passion Butterfly. They feed exclusively on species of passionflower.
The caterpillar is mainly orange with black rings is a Seirarctia Echo caterpillar. This caterpillar will turn into a Echo Moth.
The caterpillar with long black hairs on its body is likely a woolly bear caterpillar.
The black bug with long antennae can be distinguished from other insects in its habitat by its specific color and the length of its antennae.
A black bug without antennae that is not a cockroach could be a variety of insects, but one common possibility is a beetle, such as a darkling beetle or a ground beetle. These insects can often appear black and may not have prominent antennae. Another possibility is a type of black fly or certain species of aphids that may have reduced or absent antennae. Proper identification often requires close inspection or further details about the bug's size and shape.
The caterpillar that is black with a lime green jacket is the Saddleback Caterpillar. These caterpillars can sting and it will be very painful.
There are over 70 different species of caterpillars and butterflies, but I strongly believe that the caterpillar you are describing is simply the Monarch Butterfly, one of the most well-known species of butterfly on Earth. The caterpillar of such, is all black with different shades of orange and yellow stripes lining its back and neck. It has two tiny antenna on its black head. See attached page for more information: http://www.monarch-butterfly.com/