When students read in a language they are learning, they often read slowly and carefully, perhaps stopping to look up words in a dictionary or identify all the instances of a particular verb tense. This is referred to as careful or intensive reading.
In contrast, extensive reading involves reading easier material, but more of it:
Extensive reading can benefit language learners in a number of ways:
This is not to say that you should abandon careful or intensive reading altogether. But it is important to understand the difference so that you can choose appropriate materials and strategies for both intensive and extensive reading. A text that might work well for intensive reading could be too difficult for extensive reading. If that’s the case, find something easier for your extensive reading, and have fun with it!
In some Five College Center for World Languages courses, intermediate and advanced students choose reading and listening materials as part of their weekly assignments. It is usually most effective to do a mix of both careful or intensive reading and extensive reading.
Even if it is not part of your specific assignments, you might find extensive reading to be a helpful (and enjoyable) supplement to your other language-learning activities, or a fun way to help maintain your language abilities during breaks. As with other language-learning activities, it is most effective to spread your reading out over time (ideally doing a little bit every day, rather than leaving it all for the day before your conversation session).
You may also want to read Choosing Materials for Extensive Reading.