Fundamental attribution error
The fundamental attribution error is when we explain other people's behavior by overemphasizing their personality or character and underemphasizing the situation they were in. For our own behavior, we do the opposite—we blame the situation more than ourselves. So we see others as "that kind of person" while we see ourselves as reacting to circumstances.
Examples
Someone cuts you off in traffic and you think "what a rude person"; when you cut someone off, you think "I had no choice, I was late."
A colleague is late to a meeting and you assume they are disorganized; when you are late, you focus on the train delay or the emergency call.
A student who fails an exam is seen as lazy or unintelligent; when you did poorly in the past, you remembered the difficult questions or lack of time to prepare.