Amphibian.com

He didn't say he hired a good plumber.

Javascript has a weird (if you ask me) way of handling overflows - it just pegs values to the max (until it doesn't). If you have a numeric variable and you add Number.MAX_VALUE to it, your variable will be equal to Number.MAX_VALUE. Add 50 to it. Still equal to Number.MAX_VALUE. Add 1000. Same. But multiply it by 2, and now it equals Infinity. Sure, Javascript. Whatever.

Oh, and sanitizing user inputs means making sure there's no unwanted characters and strings in it that could lead to injection attacks. But these days, your dishwasher might be connected to the Internet and have its own web-based user interface, so it might need to sanitize your dishes and your input.