Image Use in Social Network Communication: A Case Study of Tweets on the Boston Marathon Bombing

Introduction. This study aimed to understand how images are used in communication practices in the Twitter environment. Method. 1,428 Boston marathon bombing related Twitter messages with embedded images were collected, and content analysis was conducted. Analysis. Characteristics of image use were examined and were analysed by type of Twitter messages. Results. People used diverse types of images in Twitter messages including: direct photos, captured images, computer graphics, and maps. Depending on the content of Twitter messages, uses of images were categorised into four types: 1) to illustrate news, information, and anecdotes, 2) to disseminate visual information that cannot be provided through words, 3) to express emotions/opinions, or to call for action from the public, and 4) to add visual components to emphasise text messages. 45% of images enclosed text within them. In some images, text and visuals were equally important in conveying messages, and showed complementary relationships; whereas in other images, text was used to direct readers on how the image ought to be read. There were also images in which text was the main information, and the visual components just provided a supplementary context. Conclusions. Image retrieval research should include diverse types of images. Also, further understanding on the relationships between visual components and text might enhance image retrieval