You can even see the two used in the same sentence, "He effected a reorganization of the department and many of the people there were significantly affected."

Effected means to actually do something, to execute, produce or bring about something. It's an action word of actually doing something, i.e. "He effected a reorganization of the finance department." Affected is used to describe something being impacted. This is a word you would commonly use when something has been impacted, i.e. "The accountants in finance were affected by the reorganization." You can even see the two used in the same sentence, "He effected a reorganization of the department and many of the people there were significantly affected." They're essentially pronounced the same so this can lead many people to get them flipped when writing them. Keeping them straight can be difficult but keeping on top of them will ensure your communications are grammatically correct.