What is a memory?

Memory is the brain’s ability to recall information from the past and it generally falls into three categories – sensory, shortterm and long-term.
Take a look at this page then close your eyes and try to remember what it looks like. Your ability to recall what this page looks like is an example of your sensory memory. Depending on whether or not this page is important to you will determine how likely it is that it will get passed on to your short-term memory.
Can you remember the last thing you did before reading this? That is your shortterm memory and is a bit like a temporary storage facility where the less-important stuff can decay over time, whereas the more important stuff can end up in the long-term memory.
Our senses are constantly being bombarded with information. Electrical and chemical signals travel from our eyes, ears, nose, touch and taste receptors and the brain then makes sense of these signals. When we remember something, our brain refires the same neural pathways along which the original information travelled. In this way, you are almost reliving the experience by remembering it.