She told the leader of the band that she was studying journalism and that her dream was to write for Rolling Stone Magazine.

journalism 是由名词 journal（期刊、日志）加上后缀 -ism（表示"学科、主义"）构成的名词，字面意思是"期刊相关的学问"，指"新闻学"这个专业领域，包括新闻采访、写作、编辑等工作。