Not a Chip

We receive the mark when we worship the beast. The mark therefore is a spiritual mark.

And the third angel followed them, saying with a loud voice, If any man worship the beast and his image, and receive his mark in his forehead [thoughts], or in his hand [deeds], the same shall drink of the wine of the wrath of God, which is poured out without mixture into the cup of his indignation; and he shall be tormented with fire and brimstone in the presence of the holy angels, and in the presence of the Lamb: and the smoke of their torment ascendeth up for ever and ever: and they have no rest day nor night, who worship the beast and his image, and whosoever receiveth the mark of his name.
- Revelation 14:9-11 (KJV)

Note how it clearly says "in the forehead", and not "on the forehead".

Worship = reverence [deep respect] + adoration [love]

God has a set day for worship.

And it shall come to pass, that from one new moon to another, and from one sabbath to another, shall all flesh come to worship before me, saith the Lord.
- Isaiah 66:23 (KJV)

Satan wants to be worshipped, so if the Sabbath is the worship day of God, satan wants to have his own worship day.

And he shall speak great words against the most High, and shall wear out the saints of the most High, and think to change times and laws: and they shall be given into his hand until a time and times and the dividing of time.
- Daniel 7:25 (KJV)

In 321 AD the antichrist changed the worship day from Sabbath to Sunday (satan's chosen day of worship).

Of course the Catholic Church claims that the change [from Sabbath to Sunday] was her act. And the act is the mark of her ecclesiastical power and authority in religious matters.
- Faith of Our Fathers, p. 14 C.F. Thomas, Chancellor of Cardinal Gibbons

And that's the test of loyalty that God will put before everyone in the last days. You either keep the commandments, and worship God on the Sabbath (no matter what happens), or you worship the beast on Sunday.

The mark of the beast = knowingly keeping Sunday instead of Sabbath.

To learn more, please watch this video.