I use the trusty brain. It knows exactly which language it wants to speak in, it knows which accent I am using, it knows which style of voice I am using and above all it will never break down in the sense of having a software crash (other break downs are unavoidable).
You're lucky. Wait until you get older. You will find that the old brain frequently malfunctions.
The spell checker is simply a tool to help people whose spelling or typing is not so hot. It can't correct grammar or similar sounding words used in the wrong context - like to, two & too. It's an optional feature which can easily be disabled if you prefer not to use it.
Things are very different now from when I was at school. Back then all school work was written in longhand & the only spell checker was your brain & a dictionary. Work containing too many errors or corrections was rejected which meant doing it all over again until we got it right. We soon learnt to check our work carefully before submitting it.
I have to admit that the spell checker has made me lazy. It found several typing errors in this reply which saved me revising it before pressing the Post button.
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