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I'm not sure whether to use :first or :eq(0) in a selector. I'm pretty sure that they'll always return the same object, but is one speedier than the other? I'm sure someone here must have benchmarked these selectors before and I'm not really sure the best way to test if one is faster. Update: here's the bench I ran: /* start bench */ for (var count = 0; count < 5; count++) { var i = 0, limit = 10000; var start, end; start = new Date(); for (i = 0; i < limit; i++) { var $radeditor = $thisFrame.parents("div.RadEditor.Telerik:eq(0)"); } end = new Date(); alert("div.RadEditor.Telerik:eq(0) : " + (end-start)); var start = new Date(); for (i = 0; i < limit; i++) { var $radeditor = $thisFrame.parents("div.RadEditor.Telerik:first"); } end = new Date(); alert("div.RadEditor.Telerik:first : " + (end-start)); start = new Date(); for (i = 0; i < limit; i++) { var radeditor = $thisFrame.parents("div.RadEditor.Telerik")[0]; } end = new Date(); alert("(div.RadEditor.Telerik)[0] : " + (end-start)); start = new Date(); for (i = 0; i < limit; i++) { var $radeditor = $($thisFrame.parents("div.RadEditor.Telerik")[0]); } end = new Date(); alert("$((div.RadEditor.Telerik)[0]) : " + (end-start)); } /* end bench */ I assumed that the 3rd would be the fastest and the 4th would be the slowest, but here's the results that I came up with: FF3: :eq(0) :first [0] $([0]) trial1 5275 4360 4107 3910 trial2 5175 5231 3916 4134 trial3 5317 5589 4670 4350 trial4 5754 4829 3988 4610 trial5 4771 6019 4669 4803 Average 5258.4 5205.6 4270 4361.4 IE6: :eq(0) :first [0] $([0]

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