Confused by Taylor Swift hype over ‘The Eras Tour’? A superfan is here to help explain it all.

The number 13 has long held a special place in Swift’s heart and she often references it. In 2009, Swift told MTV News that 13 is not only the date of her birthday (Dec. 13, 1989), but is also a lucky number that has links to many of her career successes. For example, her first album went gold in 13 weeks and her first top-charting song had a 13-second intro, she told MTV News.

During past tours and live performances, Swift has drawn 13 on the back of her hand. She even wore a New England Patriots jersey bearing the number during her first show at Gillette Stadium, which was 13 years ago. She continues to incorporate the number into her work, sometimes as a hidden message known as one of her signature Easter eggs.

Many fans are leaving shows not just with concert merchandise but homemade souvenirs in the form of friendship bracelets. The bracelet-making and trading trend was inspired by a lyric from “You’re On Your Own, Kid,” from Swift’s most recent album, “Midnights.” In the song, she sings, “So make the friendship bracelets, take the moment and taste it.” Fans took those words to heart and have been making the bracelets at home — many showing off their creations on social media — and meeting others during concerts to exchange them. Swifties have also given them to celebrities in attendance.

Fans have been clamoring to get their hands on “The Eras Tour” merchandise, particularly items that are sold only at shows and not available online. Many fans (or their parents) have gotten in line well before sunrise — as was the case Thursday at Gillette Stadium — out of fear the most-prized items would sell out. Perhaps the most popular piece of merchandise is a modest blue crewneck, which has gained cult status after fans showed it off on TikTok.

It all started in Glendale, Ariz. — the first stop on “The Eras Tour.” Sue Bredding, the city’s communication director and a Swift fan, told the Wall Street Journal that she wanted to acknowledge the city’s status as the first stop and that Swift was the first artist to sell out two nights at its State Farm Stadium. So the idea to temporarily name Glendale “Swift City” was born. Since then, other cities have jumped on board.

Las Vegas displayed a Swift-inspired light show at the Gateway Arches; Tampa, Fla., presented Swift a key to the city and invited her to be mayor for the day; Nashville honored her with a bench at Centennial Park and issued a proclamation recognizing “Taylor Swift homecoming weekend”; and Arlington, Tex., offered her a key to the city and renamed Randol Mill Road to Taylor Swift Way for the weekend.

Gillette Stadium has changed its name on social media to “Gil13tte Stadium (”Taylor’s Version”) and its biography to proclaim itself as the “home of Taylor Swift’s first NFL stadium show.”

Throughout Swift’s groundbreaking career, each album cycle has been defined by its own aesthetic, sound, and how she is perceived by her fans. For “The Eras Tour,” Swift is revisiting her past and exploring her present on stage, both in terms of the production and the songs she performs. (Spoiler: don’t expect the eras to be in order, or for each to receive equal attention.)

Swifties are nothing if not creative.

While not every fan approves of chanting during specific songs, a fair amount take part. Some started organically at shows, spread on social media, and then became popular. Others were inspired by her own music and live performances, including chanting “Taylor, you’ll be fine,” during “Anti-Hero” (inspired by the remix with the Bleachers) and clapping during “You Belong With Me.”

With the advent of TikTok, dances have also become popular. Some of the more well-known routines have been choreographed by Mikael Arellano, whose dance to “Bejeweled” went viral. Swift performed the dance at her show in Philadelphia and afterwards gave Arellano the hat she wore while singing “22.”

For some fans — and even Swift herself — a rain show only heightens the drama of the event and overall excitement. One of her most legendary performances happened at Gillette Stadium on June 25, 2011, during the “Speak Now Tour,” when Swift performed about half the show in the pouring rain. She has since called it one of her greatest memories and some fans are hoping for another rain show this weekend.

She performed her first rain show of this tour in Nashville, telling the crowd that it’s “such a bonding experience” and joking that “we all look like river otters.” Fans applauded her for sticking it out despite the weather rather than canceling the show.

Fans are known for going all out at Swift concerts, with outfits involving weeks or even months of planning. Some Swifties put their crafting and sewing skills to work, to replicate outfits Swift has worn onstage, at events, on magazine covers, and in music videos (the “Junior Jewels” tee from “You Belong With Me” is a classic). Others like to have fun with it — for instance, dressing up as a fridge (listen to “All Too Well” to understand) or one of her cats (Meredith Grey, Olivia Benson, and Benjamin Button).

Swift, meanwhile, goes through an impressive number of outfits during “The Eras Tour,” wearing an assortment of designers including Oscar de la Renta and Versace. The fashion extravaganza has left fans in awe over the quality of her outfits and the speed of her wardrobe changes as she transitions through the eras.

You may recall the absolute frenzy over tickets to “The Eras Tour.” Ticketmaster repeatedly malfunctioned, prices instantly surged to staggering heights on the secondhand market, and shows sold out in no time. Unable to see the show, fans have done the next best thing, gathering outside venues in huge numbers to soak up the anticipation. Swifties have also tuned in to livestreams broadcast by fans at the show on social media. The trend is so popular that Taylor Nation, Swift’s management team, capitalized on it to announce the release of “Speak Now (Taylor’s Version)” on July 7.

On the opening night of the tour, Swift announced she’d be performing two surprise songs during an acoustic set at each show, bringing the setlist to 44 songs. The show spans more than three hours. Swift has made a few caveats so far, saying she reserves the right to perform a song more than once if she feels disappointed with the initial performance or if it’s a song from her latest album, “Midnights.”

She’s done this before, but the suspense seems higher this time, with fans tuning in every weekend to find out what the surprise songs are, and likening the choices to the boom of the cannon during “The Hunger Games” to signal fallen tributes.

It’s fair to say Swift has her share of famous pals and many have turned up at her shows this tour, including actress Emma Stone, singer Shania Twain, and longtime friend Selena Gomez.

Swift has also brought a surprise guest to perform with her onstage at select shows, including Marcus Mumford in Las Vegas, Aaron Dessner in Tampa and Nashville, and Phoebe Bridgers, a tour opener who has joined Swift to perform their duet “Nothing New.”

Shannon Larson can be reached at shannon.larson@globe.com. Follow her on Twitter @shannonlarson98.