HTML Images: Rounded Corners, Shadows, and Gradients
Gives tips on displaying images in HTML with rounded corners and shadows and gradients
Use the border-radius option to make the corners rounded. The greater the value, the more rounded they will look. An example:

<img style="border-radius:10px" src="myimage.jpg">

and if you also want a shadow, you can add border-radius

<img style="border-shadow:20px" src="myimage.jpg">

and both using

<img style="border-radius:10px;border-shadow:20px" src="myimage.jpg">

and for fun, if we want a background image to have a gradient then we can also use the following

background:radial-gradient(#a1e048, #6a942f);

background:linear-gradient(#a1e048, #6a942f);

background:linear-gradient(to bottom right, #a1e048, #6a942f);

for creating radial and linear gradients (top to bottom) from one color to another.

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