To scan is to read quickly in order to locate specific information. The steps involved in scanning are the following:

1. decide exactly what information you are looking for, and think about the form it may take. For example, if you want to know when sth happened, you world look for a date. If you want to find out who did sth, you would look for a name.

2. Next, decide where you need to look to find the information you want. You probably would not look for sports scores on the front page of the newspaper, nor look under the letter S for the telephone number of Sam Potter.

3. Move you eyes as quickly as possible down the page until you find the information you need. Read it carefully.

4. When you find what you need, don’t read further.

Skimming

It is sometimes useful to obtain a general impression of a book, article, or story before deciding whether or not to read more carefully. To skim is to read quickly in order to get a general idea of a passage. Unlike scanning, which involves searching for details or isolated facts, skimming requires you to note only information and clues that provide an idea of the central theme or topic of a piece of prose.

When you skim, it is necessary to read only selected sentences in order to get the main idea. You should also use textual clues such as italicized or underlined words, headlines or subtitles, spacing, paragraphing, etc. Do not read every word or sentence.

Once you have a general idea about an article, you may decide to read the entire selection carefully, or only to scan for specific pieces of information in order to answer questions that have occurred to you.