Blood stain categories :
There are three main categories that bloodstain patterns fall in. They are:

-Passive Bloodstains: These are formed by the force of gravity. It can be further divided into:

-Drops: This is formed by gravity alone. It has no other influences.

-Drip patterns: This is formed when blood drips into blood; it forms a new pattern.

-Pools: This is when the blood drip stay stationary for a long period of time.