Familiarity heuristic

The familiarity heuristic is a mental shortcut or rule of thumb that helps us make decisions. When we use this rule, we make decisions based on how familiar something is to us: if something is familiar, we think it is safe, trustworthy, or favorable. To give an example, if you're at the store looking at two types of cereal, one brand is familiar to you and the other is not, you are more likely to buy the familiar brand. This is because you know that you like the familiar brand, so you think it's better.