Card Scanners vs. Touch Screens
Modern voting systems are electronic, but the involvement of a computer doesn't necessitate a fancy touch screen voting box. For example, from the 1960s up until the year 2000, many voting locations in the United States used punch card systems to tabulate votes. Once a card has been punched, it's tabulated by a computer. Voila! Results. The 2000 election between Al Gore and George Bush illuminated a problem with punch cards that has caused most states to abandon the technology: Punching systems sometimes fail to fully pierce the ballot. Without a solid punch, a computer couldn't effectively count a vote.
Since 2000, many polling places have moved on to touch screen voting devices, which are more modern e-votingsystems. These easily eliminate the hanging chads (incomplete ballot punches) and dimpled punch cards that caused counting errors in 2000, and also avoid confusing butterfly ballots, which present candidates in awkwardly offset columns that make it hard to tell who you're actually voting for. With a touch screen, you just press the right name. At least, that's how it should work.
Punch cards were around for decades, but touch screen voting machines are a comparatively new technology. In 2008, some improperly calibrated touch sensors caused voters to accidentally vote for the wrong candidates [source: Zetter]. Electronic systems pose another challenge we'll get into on the next page: Should votes be tabulated on the machine, or sent over a network to a central tabulation location?