Field Of View, AKA FOV. A setting to change your size of field view. The higher it is, the more you will see around you.

The Default FOV is very bad, it's set 75 by default and the setting's slider goes to a max of 90 it's should be set on 90 by default, this gives everyone with default a disadvantage as you can't see much, so your more likely to die from spy's, snipers, Sentries and Stickybombs because you couldn't see them.

If you have a default FOV as 75, you should change it. How, you ask?
Its easy:
1. Open developer console. Dunno how?
1.1 Open Settings.
1.2 Find and click "Advanced"
1.3 Then make sure "Enable Developer console" box is checked.
There you go! You enabled developer console! Good job, so far!
2. Click `~ key on your keyboard, it's right below your "Escape" key, AKA "ESC" key.
3. Console opened? Good. Now to change FOV copy&paste this command:
viewmodel_fov x
4. Once you copy&pasted it, just replace the X with a number, mostly recommended is 90. As if you go higher, your character arms will start detaching, and will seem to be flying. Well all depends on you.
5. Now press "Enter" key, and close console.
6. Good job! You've done it! Now you've got a proper FOV and you might get better at the game!
Anyways thank you for using this guide. Hope it helped everyone!
And have a beatiful day!
P.S: For those who are curious, the FOV applies everywhere, it doesnt depend on sv_pure -1,0,1,2 in the server, and also applies to VALVE servers and all characters!