its, it's their, there etc. but the worst is amature instead of amateur (and usually the writer
is crying about how hard the license exam is).
No matter how hard you try to fix people we are all just part of the great unwashed.
Their, they're, there
Too, to, two
Lose, loose (they don't even sound the same)
And many more.
But there are worse things.
There's the person who uses various logical fallacies as "proof" of their statements. Appeal to Authority, ad-hominem, false dichotomy and many more get used.
Then there's the person who posts provably incorrect information as fact. And of course the person who unleashes personal insults at those who dare to point out an error or even have a difference of opinion.
For example, some time back there was an article in which a poster stated that HF antenna tuners were inefficient by nature. He claimed that all they did to improve the SWR seen by the rig was to convert the reflected power to heat. He claimed that the *only* way to have an efficient system was to use a resonant antenna, matched at the antenna.
All sorts of examples and analyses were given to disprove his claim, yet he stuck to it and insulted all who opposed him. He claimed experience in non-amateur radio as his proof - classic Appeal-to-Authority fallacy.
In another case, it was stated that glass transmitting tubes such as the 3-500Z would *always* last longer if operated well below ratings, and that operation with the anode showing visible color shortened the life of such tubes.
It was pointed out by several others that *some* glass transmitting tubes such as the 833A and 3-500Z have the anode coated with gas-adsorbing materials such as zirconium. For proper gettering action in those tubes, the anode should operate at or above the temperature where it begins to show some color.
Manufacturer's data and application notes were cited, including a paper that clearly explained the whole process. Yet some folks simply refused to accept the facts, and insulted those who posted the correct information.
Then there's the why-hams-use-LSB-on-75-but-USB-on-20 myth...
73 de Jim, N2EY