The ellipses indicate services (taken from the UML use-case icon) and the lines are flow of control and messages (roughly).

椭圆表示服务(取自uml用例图标)，而线条则是控制和消息的流(同上)。

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This is built-in to your XP already and is accessible from the Display icon in the Control Panel from the Appearance TAB.

这个主题是XP自带，可以通过“控制面板”下的“显示”图标中的“外观”属性一栏获取。

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Click the desk icon or press Control + s to save the file.

点击桌面图标或者点击Control + s以保存文件。

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The music note icon in the bottom left corner of every page makes it easy to control audio tracks from anywhere in Flipboard.

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However, the beloved Yankee icon and former captain has taken everything in stride and focused solely on the matters that he can control.

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Even on WiFi, control feels laggy, and there's no native guide (though there's an icon to quickly pull up your set-top box's guide).

ENGADGET: SlingPlayer Mobile for iPhone coming shortly: $29.99, no 3G support