Credit cards, gift cards, and hotel access key cards are some of the common items that use magnetic stripe technology. Magnetic stripes (or magstripes) consist of a film with millions of magnetic particles suspended within it. Card manufacturers apply this film to cards. The manufacturer then encodes the magnetic area of the card with alphanumeric symbols. Once it’s encoded, the card is ready to swipe!
Hico vs Loco
Coercivity is the ability of a magnetic material to withstand an external magnetic force. A unit called an Oersted measures magstripe coercivity.
Hico is simply shorthand for HIgh COercivity. A hico mag is more resistant to the effects of a magnetic field. The higher the coercivity of the magstripe, the harder it is to erase the information that’s stored on it. Hico cards have a resistance of 2750 Oerstead.
Hico magstripes are important for applications that require you to keep information stored for a while. Credit/debit cards, gift cards, security access cards, and employee ID cards use hico technology.
Similarly, loco is an abbreviation of LOw COercivity. Loco cards have a much lower resistance of 300 Oersted. Loco cards are easier to reprogram because of this lower coercivity. This ability to easily rewrite makes them ideal for applications like hotel key cards and amusement park passes.
Hico magstripes are more expensive than loco due to their higher resistance.
What Kind of Information is Written on Magstripes?
There are up to three tracks on any given magstripe. Each track stores a specific amount of information.
- The first track supports up to 76 alphanumeric data characters.
- The second track supports up to 37 numeric only data characters.
- The third track supports up to 104 numeric only data characters.
How Many Tracks Do I Need?
Most card applications require at least 2 tracks. Your Point of Sale provider can give you more specific information on the magstripe requirements for your gift cards.
References:  howstuffworks,  Magtek