Just as Superman is the prototype of all future superheroes, Lois Lane was the model upon which further love interests would be molded after.
Throughout the Multiverse there were two known quite well, of Earths One and Two. The first Lois was a lead reporter for the Daily Star, the second Lane was a lead reporter for the Daily Planet. Each met their Dreamboat of Steel, and frustrating romances developed from there.
The daughters of Sam and Ella Lane, each Lois had a sister...the younger one's was flight attendant and sometime Jimmy Olsen girlfriend Lucy... the younger housewife Lucille and mother of Susie Tompkins.
While Earth-Two's Lois Lane had a solo series in the back pages of Superman during the 1940's, her sister soulmate of Earth-One had own her own self-titled comic followed by a series in Superman Family and Supergirl's back pages. The latter faced far more unorthodox adventures than had her predecessor, although both donned the guise of Superwoman on more than one occasion. And while the silver age Lois had to contend with her beau Superman's childhood sweetheart Lana Lang from early on in her career, the golden age Lois met Lana after she had already married her man hence there wasn't the budding rivalry between those two as had existed amongst the younger pair.
When circumstances, and criminals, conspired behind the scenes to remove Superman from Earth-Two, Clark Kent remained and gained a new found heroism in his nature. This prompted Lane to marry Kent, soon after discovering that her amnesiac husband was the Big Blue Boyscout. Decades later, they unofficially adopted Kara Zor-L from Krypton-Two when she finally arrived, prior to her debut as Power Girl. The Earth-One Lois had a more prestigious career, and more frustrating romance, with her own Man of Steel... later losing out to Lana once more before a Crisis forced her back into her love's arms while her counterpart and her husband became exiled in another dimension to escape the catastrophe of Infinite Earths the enveloped the Multiverse.
Despite their differences, at their core were two women with tremendous tenacity, and a determined devotion towards their craft as ace reporters. Yet it was their strength and compassion that drew their worlds' greatest champion close to their hearts.