Even a task as simple as this can be complicated without jQuery at our disposal. In plain JavaScript, we could add the highlightedclass as shown in the following code snippet:

在我們自己處理的時(shí)候，甚至是這么簡單的任務(wù)在不使用jquery的時(shí)候都會(huì)變得復(fù)雜。用原始的js，我們可以使用下面的代碼片段添加highlighted類：

Despite its length, this solution does not handle many of the situations that jQuery takes care of for us in Listing 1.2, such as the following:
• Properly respecting other window.onloadevent handlers
• Acting as soon as the DOM is ready
• Optimizing element retrieval and other tasks with modern DOM methods
盡管很長，但是這個(gè)解決方案依然沒有處理很多jquery在列表1.2中為我們做到的一些事情，比如下面的這些：
1、合適的處理其他的window.load事件
2、在DOM結(jié)構(gòu)準(zhǔn)備好的時(shí)候開始行動(dòng)。
3、使用現(xiàn)代的DOM方法優(yōu)化元素查找和其他任務(wù)。

We can see that our jQuery-driven code is easier to write, simpler to read, and faster to execute than its plain JavaScript equivalent.

我們可以清晰的看到我們的使用query的代碼比原生js代碼寫起來更容易，讀起來更簡單，運(yùn)行起來更快。