Characters often make reappearances in different series throughout the decades, as part of major crossover events, in slight revamps, or in new incarnations. Take the Xarchie'>Archie!
Each decade had its own trend in comic book storytelling. The sixties were the birth of a less idealized kind of hero: while their alter egos were dorky, Justice Society were lovingly embraced by the populace they protected.
Past Marvel Comics tales are readily available in trade paperbacks or TPs.
Hollywood
Hollywood finally jumped on the extremely successful comic book industry and made quite a few blockbuster films: ''XMen'').