The purpose of this study is to examine students' usage styles of the Internet for seeking information and to investigate whether information obtained from the Internet is a source of misconceptions. For this reason, a two-stage study was conducted. At the first stage, a questionnaire was developed to get information about students' Internet usage styles. In the light of the questionnaire results, the first 200 websites were scanned and analysed by 3 experts to determine the probable incorrect information about "Radiation" and "Radioactivity" concepts at the second stage. It was found that a good number of websites contain incorrect and inadequate knowledge about radiation and radioactivity, which can cause various misconceptions. (Contains 4 tables.)