Why is it important to specify image sizes in software code?

Setting image dimensions in code is important for several reasons:

1. Performance optimization — the browser or application knows in advance how much space to allocate for the image, helping to avoid layout recalculations (reflow) during loading.
2. Preventing content shifts — if sizes are not specified, the page may 'jump' during image loading, degrading user experience.
3. Improving SEO and accessibility — search engines and assistive technologies handle pages with correctly specified sizes better.

Example in HTML:

<img src="photo.jpg" width="600" height="400" alt="Description">

Here, the browser reserves an area of 600x400 pixels for the image immediately.