Before viewing any pictures it is very important that you calibrate your monitor so that you can see all the shades of tone in an image. The grey scale image will help you to do this.

The values of grey are:
2%-5%-10%-20%-30%-40%-50%-60%-70%-80%-90%-95%-98%

Along the bottom runs a Black (0%) and White (100%) bar for comparison.
The surround is 50% grey so that the eye is not distracted by nearby coloured areas next to the bars.

Use the monitor brightness control to set the left-most bar to be almost but not quite black and then use the contrast control to set the brightness of the white bar. The right-most bar should be almost but not quite white but if it becomes completely white then reduce the contrast or adjust the gamma controls of your monitor or graphics card until it is slightly grey again.

Finally, look at the mid-tones around 30%-60% and check that they actually look grey. Any imbalance in the red, green, and blue output of the monitor screen will show as a colour cast - some shades of grey might have a green tinge and so on.

If you can see colour in any of the grey scale then you may need to adjust the colour temperature of the monitor (some digital models have presets - mine is set for 9300K or "daylight"). Otherwise, you may have controls to vary the individual colour gamma of red, green, or blue output of either the monitor or graphics card. Failing that you could just live with itů

When you're done you'll be ready to enjoy photographs of all kinds - not just mine!