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Number MAX_VALUE and Number MIN_VALUE define the outer bounds of the Number value set

All numbers must fall between Number.MAX_VALUE and Number.MIN_VALUE. When a calculation results in a number greater than Number.MAX_VALUE, it is assigned a value of Number.POSITIVE_INFINITY. When a calculation results in a number less than Number.MIN_VALUE, it is assigned a value of Number.NEGATIVE_ INFINITY. If a calculation returns an infinite value, the result cannot be used in any further calculations. There is a special value for infinity named Infinity. Number.POSITIVE_ INFINITY has a value of Infinity. Number.NEGATIVE_INFINITY has a value of -Infinity. A method can be used to determine if a number is finite. var iResult = iNum* some_really_large_number; if (isFinite(iResult)) {     alert("Number is finite."); } else {     alert("Number is infinite."); } The perils of Javascript - Number.MIN_VALUE from lodge.stuart at gmail.com Just spent some time debugging a problem.... I had a filter set up in my new player code on runsat - and when the filter was disabled I was setting  the filter limits to Number.MIN_VALUE and Number.MAX_VALUE. I thought this would be fine because several site like  http://www.rntsoft.com/Tutorial/JavaScript/0100__Number-Data-Type/NumberMAXVALUEandNumberMINVALUEdefinetheouterboundsoftheNumbervalueset.htm say things like:     When a calculation results in a number greater than Number.MAX_VALUE, it is assigned a value of Number.POSITIVE_INFINITY.     When a calculation results in a number less than Number.MIN_VALUE, it is assigned a value of Number.NEGATIVE_ INFINITY. However.... this is complete "codswollop" - actually MIN_VALUE is an epsilon value - it's the smallest positive fraction allowed in javascript - so it's not negative - in fact it's almost (but not quite) zero. Looking around loads of sites contain big info on this! Yikes!