This chapter will tell us how to work with spans of text that typically cover one or more words/tokens. The LingPipe API represents this unit of text as a chunk with corresponding chunkers that produce chunkings. The following is some text with character offsets indicated:

LingPipe is an API. It is written in Java.
012345678901234567890123456789012345678901
          1         2         3         4           

Chunking the preceding text into sentences will give us the following output:

Sentence start=0, end=18
Sentence start =20, end=41

Adding in a chunking for named entities adds entities for LingPipe and Java:

Organization start=0, end=7
Organization start=37, end=40

We can define the named-entity chunkings with respect to their offsets from the sentences that contain them; this will make no difference to LingPipe, but Java will be:

Organization start=17, end=20

This is the basic idea of chunks. There are lots of ways to make them.