Common Errors in English Usage

I am by no means an English expert and do not claim to always write or speak correctly.  However there are a few misuses of the language that I find particularly annoying and would like to help clear up.

Here is my list, in no particular order:

•  Using "would of" instead of "would have". I know why people make this mistake. It's because when you speak the contraction "would've" it can be mistaken for "would of" so then people write it that way.
• Using "I could care less" instead of "I couldn't care less". The first one implies that you actually do care and it's possible for you not to care as much. The second implies that you care so little that you could not possibly have any less care, which is usually what people mean to say in this case; essentially "I don't care"
•  Misuse or misspelling of "Etc.", "e.g.", and "i.e.". All are abbreviations for Latin phrases. "Etc." stands for "Et cetera" and means "and so forth". It can be used in cases such as "I bought some produce: apples, bananas, oranges, etc.".  "e.g." stands for "exempli gratia" and means "for example". It can be used such as "You should buy some produce, e.g. a banana".  i.e. stands for "id est" and means "that is" or "in other words". It can be used such as "I bought some produce, i.e. some fruit and vegetables".
• Misuse of "a/an". This one I don't see as much and usually only from people that don't have English as their first language. Basically if the word after "a/an" begins with a vowel or vowel sound, use "an". Otherwise use "a". This applies to acronyms as well: "An MRI" (vowel sound), "A GTO". Now, if the word begins with "H" but the "H" is not pronounced, this making it a vowel sound, use "an": "An honest mistake" vs. "A historic event".
• Effect/Affect. I will give you some slack on the confusion for this one. There are multiple rules about these. However, the most common use is "effect" as a noun and "affect" as a verb. "The effect of the movie was great". "The movie affected me greatly".
• Advice/Advise. Advice is a noun, Advise is a verb. "I gave them some advice". "I advised them".
• Accept/Except. Accept means to consent or agree. Except means to exclude.
• There/Their/They're. This is a big one. There is an adverb: "He is over there", "There is one".  Their is possessive: "They like their beer cold".  "They're" is a contraction for "They are".  "They're driving the car".  All three: "They're taking their belongings over there"
• Won't/Want. Won't is a contraction for "Will not". Yes I know it doesn't make sense but it's true. "I won't go!".  Want is most commonly a verb: "I want to go".
• You're/Your. You're is a contraction for "You are". "You're going to sit over there".  Your shows possession. "That's your favorite!".
• Viola/Voila.  A viola is a flower or musical instrument. What you are probably looking for is "voila" which means "behold!". It comes from a French expression meaning "look there!".
•  Disc/Disk.  Disc refers to a compact disc, or CD which is read and written optically. Disk refers to a hard disk drive (HDD), or less commonly a floppy disk drive, both read and written magnetically.
• Download/Upload. Me being a computer geek, this one bugs me more than some. Downloading is transferring files to your computer; uploading is transferring from your computer. So, you download a picture from the internet, as well as download files from a CD or jump drive to your computer, but you upload pictures to Facebook. The same file can be referred to as being downloaded or uploaded depending on which computer you are using: the sending one (upload) or the receiving one (download).
• It's/Its.  It's is a contraction for "It is": "It's very cold outside".  "Its" is a possessive pronoun. "Its eyes are green". This can be confusing because generally an apostrophe and "s" is used to show possession. In this case, you leave it out.
• Weather/Wether/Whether. Weather refers to atmospheric conditions: rain, cloudiness, etc.  Whether is a conjunction: "He has to decide whether or not he's going".  A wether is a castrated ram.
• Sale/Sell/Sail.  A sale (noun) is what takes place when you sell (verb) something. Sail is the action of a boat and the name of the canvas on its mast. 

That's it for now.