When you use work created by someone else, you need to consider their copyright. This video provides a short introduction to copyright:
When you create your own work you also need to think about how to protect it from being copied by others without your consent. On the Copyright User website you can find out more about what copyright means for you as a writer, musician, filmmaker, performer, visual artist or developer. In this video you can hear from a professional photographer What Copryright Means to her.
You'll find more resources on the Library's copyright page.
Just because you found an image on the web, it does not mean that you are legally allowed to copy it and use it in your own work. Copyright is held by the artist and, unless the licence explicitly states that you can share or use the work, you shouldn't copy it without asking for the artist's permission. Find out more about Images and Copyright on the Library webpage.
Luckily several artists and photographers make their work available with more flexible copyright licences so you can use it. A good place to start to look for these images is on Creative Commons.
As a student you have access to databases with images that have been copyright cleared for use in education:
When using images created by someone else in your artwork, there is a fine line between creating a new work of art and infringing on the rights of another artist. This short video discusses the issues and explains what Image appropriation means (Falmouth login required)
In many cases you can avoid infringing someone else's copyright by acknowledging that you have used their work. To do this in academic work you need to learn how to reference your sources. There's lots of helpful information about Referencing on the ASK webpages.