My MIND.
What is a memory?
There are lots of different ideas, and questions(!), when it comes to what makes a memory, so let's start by defining 'memory':
A memory is the way the brain records and stores information, so that we are able to retrieve it at a later date.
Human's experience both short and long term memory - short-term memory are memories which stay with us only for a moment or two, for example remembering the last thing a person said to you during a conversation, or the last instruction you received. Long-term memory includes declarative memories, those which require conscious memory recall (for example, recalling facts about your favourite dinosaur), and non-declarative memory, which uses saved information without conscious awareness (such as emotional responses to environments based on past experiences).
Many different regions of the brain are involved in storing memories. This video from Neuro Transmissions explains how neurons (nerve cells) create connections which help us to form new memories.
Our brains are able to store and erase memories, but we don't remember everything, and this is a GOOD thing. Our brain is constantly receiving and processing information, and is selective about what remains, and what is forgotten.
Side quest!
If a memory is a pattern of electrical (neural) activity in our brain, the represents the experiences we have had, how accurate are our memories?
In this video, neuroscientist Lisa Genova explores how memories are stored, different types of memories, and how truthful our memories really are.