Sets whether user can select more than one row cell. If it is set to true the user can select multiple rows/cells by pressing CTRL or SHIFT keys and clicks over the row/cell. If the user selects more than one row/cell and clicks on the other without pressing CTRL or SHIFT key the previous selected rows/cells will be deselected:

    dataSource: {
        data: [
            { ID: 1, name: "name1" },
            { ID: 2, name: "name2" }
    selection: {
        type: "row",
        multiple: true
    columns: [
        { field: "ID", title: "Unique Number", format: "{0:c}" },
        { field: "name", title : "Name", width: "300px" }

Live demo of multi selection functionality you can find here: Grid Multi Selection