I press the letter o and l on my keyboard, the these are automatically accompanied by 7 And * respectively and vice versa. wha

[SwatiIyer1]

When I type the *letter 'o' its accompanied by 7 automatically similarly when I press the letter l it has * symbol with it. so if I type the words letter and symbol without editing it may look *like this
'*letter' and 'symbo7*l'

 

[Karsten75]

If it is a laptop, you have the Numlock enabled.