Historically, the understanding of the Mark of the Beast has been shaped by cultural and religious connotations. During the days of the apostle John many would have believed that the Mark of the Beast was related to the emperors of the Roman Empire. During this time some had used a mathematical numerical system known as Gematria to try and prove that emperor Nero was the fulfillment of 666. When pagan Rome eventually declined to be replaced by papal Rome many of the reformers who broke away from Catholicism viewed the seat of the Vatican as the manifestation of the beast with some then claiming that Sunday worship was the actual fulfillment of the Mark of the Beast a view held today by Seventh Day Adventist. Yet the landscape of understanding significantly shifted with 1 event which took place which has clearly put the focus on the key areas that we can look at in confidence.
The Mark of the Beast goes far beyond a corporation (MasterCard/Visa), a platform (UPC bar codes), a religion (Islam) or times and seasons (Constantine changing the day of worship to Sunday). It also goes beyond the insertion of a device into the body (microchip). All of these may or may not be ancillary representations but they are not the finality of the Mark of the Beast which is something far worse. So bad that God himself provides no way of escape, no redemption, no forgiveness, no second chance for those who take it.
Hopefully by downloading the "666 Singularity" all these pieces will come together in making sense of it all.