The JSTL <c:choose>, <c:when>, and <c:otherwise> tags provide a way to implement conditional logic in JSP pages.

The basic syntax for the <c:choose> tag is as follows:

<c:choose>
  <c:when test="condition1">result1</c:when>
  <c:when test="condition2">result2</c:when>
  ...
  <c:otherwise>defaultResult</c:otherwise>
</c:choose>

The <c:when> tags are used to specify conditions that are tested in order, and the first condition that evaluates to true causes the corresponding result to be output. The <c:otherwise> tag is used to specify a default result that is output if no <c:when> condition is true.

Here's an example that shows how to use the <c:choose>, <c:when>, and <c:otherwise> tags to implement conditional logic in a JSP page:

<c:choose>
  <c:when test="${pageContext.request.method == 'GET'}">
    <p>This page was requested using a GET request.</p>
  </c:when>
  <c:when test="${pageContext.request.method == 'POST'}">
    <p>This page was requested using a POST request.</p>
  </c:when>
  <c:otherwise>
    <p>This page was not requested using a GET or POST request.</p>
  </c:otherwise>
</c:choose>

In this example, the conditions being tested are the HTTP request method (GET or POST). The result for each condition is a different message that will be output in the HTML page.

The <c:choose> tag, along with its associated tags, provides a powerful and flexible way to implement conditional logic in JSP pages.