LOL at a lolcat and your LOL gets logged for all time on your indelible activity record.
你在一张搞怪猫的图片下面哈哈了一下，你的这个哈哈就会被一直记录在你的活动记录里了，删不掉了。
2
The original use was typed by Wayne Pearson, in Calgary, who says he wrote the first ever LOL in reply to a gag by someone called "Sprout".
最初的用法是加拿大卡尔加里的 Wayne Pearson 输入的，他说他在回复一个名叫 “Sprout” 的笑话时第一次写下了 LOL。
3
The OED defines LOL as an interjection "used chiefly in electronic communications… to draw attention to a joke or humorous statement, or to express amusement".