Visual aids are effective tools for communication as they help audiences retain information, stay engaged, and better understand concepts. Some key benefits of visual aids include improving memory retention of information by up to six times compared to verbal communication alone, maintaining audience attention spans, organizing presentations into easier to remember chunks, and aiding comprehension for different learning styles. Common types of visual aids include posters, slideshows, models, videos, presentation software, handouts, and transparencies. Effective use of visual aids requires preparation and choosing aids appropriate for the audience size and demographics.