公益广告已经存在了大约一百年。公益广告能够教育大众，提高群体意识;癌症、戒烟、全球变暖、战争、暴力，这些都是公益广告大书特书的主题。
通过视觉表现来攫取公众的注意力，这是比较常用的表现手段。图像生动直观的表达出一种隐忧，让公众如临其境的感受到：如果再不做点什么，我们的美好的世界将被一点一点的破坏。
公益广告的要点就在于：要有视觉冲击力。要有触目惊心的效果以及图像的整体感，下面就是精选的25张公益广告，在这些案例中，图像能有效的冲击视觉、唤起情绪，而且整体的意象深远。
这些广告，更像是一种呼吁、一种声明。瞧瞧哪一张震慑人心让你过目不忘呢?欢迎评论分享下：)
WWF: Tree
[flash=500,400]http://s1.knowsky.com/20160211/tn4urpxs22q58.jpg[/flash]Heart and Stroke Foundation: Future
[flash=500,400]http://s1.knowsky.com/20160211/m2gsffjnmcs59.jpg[/flash]Salvation Army: Politician
[flash=500,400]http://s1.knowsky.com/20160211/mgoj1ionmik59.jpg[/flash]Surfrider Foundation: Plastic Invasion
[flash=500,400]http://s1.knowsky.com/20160211/p0jba03wisp59.jpg[/flash]World for All: Train
[flash=500,400]http://s1.knowsky.com/20160211/i1aljf20ynz59.jpg[/flash]Dutch Heart Foundation: QR Bystanders
[flash=500,400]http://s1.knowsky.com/20160211/k551ncdavoe59.jpg[/flash]Amnesty International: Tsunami
[flash=500,400]http://s1.knowsky.com/20160211/1gkmxn3pukd59.jpg[/flash]Ecuadorian Red Cross: Life Inside Life
[flash=500,400]http://s1.knowsky.com/20160211/yn2urcshz1159.jpg[/flash]Department of State Health Services: Share Air
[flash=500,400]http://s1.knowsky.com/20160211/4ann3kxcaak59.jpg[/flash]World for All: Building
[flash=500,400]http://s1.knowsky.com/20160211/44g450nl5dg00.jpg[/flash]WWF Desertification: Elephant
[flash=500,400]http://s1.knowsky.com/20160211/cmjvmv22jts00.jpg[/flash]Amnesty International: Pencil
[flash=500,400]http://s1.knowsky.com/20160211/yxzgackvzn100.jpg[/flash]Operation Smile: Charlie Dot
[flash=500,400]http://s1.knowsky.com/20160211/sp5qofbzi2200.jpg[/flash]Safe Kids: Football
[flash=500,400]http://s1.knowsky.com/20160211/slopwft0iw500.jpg[/flash]OndAzul NGO: Sardine
[flash=500,400]http://s1.knowsky.com/20160211/ezcvpkij1k400.jpg[/flash]Operation Smile: Sally Monkey
[flash=500,400]http://s1.knowsky.com/20160211/5eiii1ij11g00.jpg[/flash]TAC: Confusion, Overpass
[flash=500,400]http://s1.knowsky.com/20160211/jlnpkecpfhe00.jpg[/flash]Samusocial: Stop the Nightmare
[flash=500,400]http://s1.knowsky.com/20160211/3an0ylazsje00.jpg[/flash]Fight for Peace: Favela
[flash=500,400]http://s1.knowsky.com/20160211/cxbz2rew2hk01.jpg[/flash]Canadian Journalists for Free ExPRession: Tara
[flash=500,400]http://s1.knowsky.com/20160211/nfwt5tf5ppv01.jpg[/flash]Pedestrian Council of Australia: Man
[flash=500,400]http://s1.knowsky.com/20160211/m0d40ppsye301.jpg[/flash]Stivoro: Open Road
[flash=500,400]http://s1.knowsky.com/20160211/zvqtaededuc01.jpg[/flash]GirlHub: Amina
[flash=500,400]http://s1.knowsky.com/20160211/jysqekua2r301.jpg[/flash]Global Warming
[flash=500,400]http://s1.knowsky.com/20160211/krvtxkpegtz01.jpg[/flash]Utah Department of Highway Safety: Alcohol Cuffs
[flash=500,400]http://s1.knowsky.com/20160211/vsomzashd2p02.jpg[/flash]Greenpeace: Become David
[flash=500,400]http://s1.knowsky.com/20160211/1jv2hnkotiz02.jpg[/flash]So Acao Solidarity Movement: Much More than Trees
[flash=500,400]http://s1.knowsky.com/20160211/5lbdzfsatl302.jpg[/flash]