What does the " \' " means in the ng-style?

what does the " \' " in the following code means ? ``` <div ng-style="{ \'cursor\': row.cursor }" ``` Why can't one just write ``` <div ng-style="{ cursor: row.cursor }" ``` The full code ``` rowTemplate: '<div ng-style="{ \'cursor\': row.cursor }" ng-repeat="col in renderedColumns" ng-class="col.colIndex()" class="ngCell {{col.cellClass}}" style="overflow: visible"><div class="ngVerticalBar" ng-style="{height: rowHeight}" ng-class="{ ngVerticalBarVisible: !$last }">&nbsp;</div><div ng-cell></div></div>', ``` I also dun understand why in the first ng-style the code uses \', and in the second ng-style the codes uses height directly without \'. Codes taken from https://github.com/angular-ui/ng-grid/issues/994