Let's create that simplified black and white effect on a photo using threshold adjustment and make a so called Internet meme or a motivational poster ready to be printed on an A4 size paper.
Image overlay pattern comes in very handy when a website has a full screen image or a video as a background. Applying a pattern can make things more readable and easier on eyes. Let's Photoshop.
If you don't want others to use your photos and images without your permission, you can create a so called custom watermark with your name or any other text you want.