Shulchan Arukh, Orach Chayim 689/שולחן ערוך·אורח חיים תרפ״ט

1That all are obligated to read megillah. Containing 6 paragraphs:All are obligated in reading [the megillah]: men, women, converts, and freed slaves. We teach the children to read.

2Whether one reads or hears from someone who reads - he has fulfilled his obligation. That is, if he hears from someone who is obligated in reading it. Therefore, if the reader was a deaf-mute, or a minor, or mentally infirm, one who hears from him does not fulfill [his obligation]. And there are those who say that women do not fulfill the obligation for men. Rema: And there are some who say, if a woman reads for herself, she blesses "to hear the megillah," because she is not obligated in reading (Mordechai first chapter of megillah)

3An androgynous person fulfills the obligation for his kind, and not for those not of his kind. A Tumtum and someone who is half slave, may not fulfill the obligation even for his own kind. Rema: There are some who say that he cannot even fulfill his own obligation, and he must hear from others. (Beis Yosef)

4One who hears the megillah from someone from whom he is sworn not to accept benefit, has fulfilled [his obligation].

5In a place with no minyan, if one [person] knows it and the rest do not, one can fulfill [the obligation] for them all. If they all know, everyone reads to himself.

6It is a good tradition to bring male children and female children to hear the reading of the megillah.