abdomen
Often called a zipper spider or writing spider.
A garden cross spider, Araneus diadematus. Source: Google search for spider cross back
The spider you are referring to is likely the black widow spider. The female black widow has a distinct red hourglass shape or white crescent on its abdomen. They are known for their venomous bite, so caution should be taken when encountering them.
Female hobo spiders appear to have diamonds on their back. Google Hobo spiders and see if that is what you are refering to.
It is called ballooning when a spider wraps its prey up.
The spider with pincers on its back is called a vinegaroon or whip scorpion.
The kind of spider that has a distinctive line running down its back is called a "striped spider."
Thorax
Its called The "Katipo spider"
a red back.
An Arrowhead spider is brown with a green back. This spider is also known as a Triangle Orb Weaver. This spider is not venomous.
The band is Shiny Toy Guns, the song itself is called Le Disko
Often called a zipper spider or writing spider.
The spider you are describing is mainly found in Australia. Its called a red back. Very Very Poisonous.
A false widow spider is a spider that is known to have a skull depicted on its back. This spider also has orange legs.
The distinguishing feature of a brown spider with a zigzag pattern on its back is the presence of a unique marking called a "zigzag" or "herringbone" pattern on its abdomen.
The zebra spider has a stripe on its back.