To summarize this text about compressing images and reducing their file sizes:

1) Compressing an image involves limiting its file size by either:

- Reducing the quality of the image (which makes it look less sharp)

- Removing hidden elements from within the image itself.

2) There are several ways to do this, including:

a) Choosing between different types of images like JPEGs, PNGs, SVGs and GIFs depending on their intended use.

b) Adjusting the file size by either reducing or increasing its resolution. For example, if you have an image that's 2000 x 1500 pixels in size then resizing it down to something smaller will make both the file size much smaller but also reduce the overall quality of your picture too!

3) The three main factors affecting how big (or small) someone sees when they open up their browser window after clicking through link pointing towards website where this particular piece content lives at first glance before moving onto next point which may not necessarily relate closely enough yet still worth mentioning just incase anyone wants know more about why certain things happen while others don't without explanation given here today either way hope above helps clarify matters slightly better now!

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