Why do some smaller boats have very tall masts?

So I was looking at a dock with several boats and noticed that many of them had very tall masts.  I don't know very much about boats, but was a bit confused about why it was necessary that they even have masts at all because wouldn't they have motors?

At first I found out about vestigial masts on larger ships.  For example warships nowadays are probably not using sails but apparently some still have masts to mount radar and other antennae.  On a smaller scale, but still fairly large, 50+ foot yachts may have forward masts to mount lights.

In my attempt to wade through the boating information I quickly discovered that there are many terms I don't know... 

Keep in mind though, that as you reduce the tack angle below 90 degrees (making the clew to luff horizontal distance shorter than the foot length) you often wind up having to install jacklines along the lower luff which ease the slugs or slides off just to be able to raise, lower or reef the sail.

What the what.  At times I was a bit over my head.

Without being able to find much information I came to the conclusion that I was probably asking the wrong question.  Thinking about it some more, sails and motors didn't have to be mutually exclusive.  It probably made sense that a sail boat with a large mast would also have a motor to help out when the winds weren't very strong or for ease in undocking.

Searching a bit more it seems like it's not uncommon for sailboats to have a motor as well for the reasons I thought of above.  So I was probably just looking at a bunch of sailboats... doh.

Onomatopoeia

A few of my joints crack at certain times.  I can crack my fingers every so often by pressing them together.  I can crack my knees my crouching down.  My neck kind of cracks a bit if I move it around in certain ways.  Obviously I'd considered that these may not be good signs for the health of my body and I should probably determine if this is normal or harmful.

Talking to other people I didn't really come to a general consensus.  Common sense seems to dictate that it wouldn't be completely harmless.  To the internet of course!  What I found was that if the joint cracking was accompanied by pain it's not a good thing.  Dehydration and vitamin and mineral deficiencies can cause cause these problems.  Fortunately for me my joint cracking isn't painful.

I found that the more benign reason that joints seem to crack has to do with air trapped within the joints.  When bending occurs in them then the air can be forced out, causing a cracking noise.  This is still not completely confirmed but it's the best theory.  And in this case the joint cracking or popping is considered fairly harmless and should not lead to arthritis!  I think I feel a bit better now.

Crows vs Ravens

Sometimes things will come up in discussion or I'll just wonder about something and then never actually take the time to look into it.  The differences between crows and ravens was one of those things; but no more.  Without reading anything my thoughts basically were that ravens were bigger.  And probably less annoying.

I haven't exactly had positive experiences with crows.  On a certain section of the walk to my high school there were some trees where crows liked to hang out.  Occasionally while walking to school I could tell they were extra agitated with their intense cawing.  Then when I wasn't looking a crow would swoop down close enough to brush against my hair.  I discovered that if I faced the crows they wouldn't swoop at me, so I would walk that section backwards if I felt threatened by them.  Ravens couldn't be any worse than that.

It appears I was not incorrect.  Apparently a raven weighs about four times as much as a crow and is noticeably larger.  Ravens make a less annoying lower pitched sound.  They also have a curved bill and more wedge-shaped tail.  Crows are more social than ravens which allows them to do better in an urban environment.  I'm not sure if I've ever actually seen a raven but they sound cool enough to me.  This video goes into more detail on the differences.

10,000

I learn new words from listening to other people speak but mostly from reading.  One word whose use slightly confused me for some time was "myriad".  Years ago I read something like "there are myriad uses for the glockenspiel".  From the context I determined that it meant something like many.  For whatever reason though, its use as an adjective made me feel slightly uneasy.

I also encountered myriad parading around as a noun!  "There are a myriad of noses on the jabberwocky".  This felt a bit more natural to me, like "a bunch of".  After reading both versions several times in different locations I determined that either way was probably acceptable.  Now years later I finally took the time to look it up (so I could write this).

Apparently myriad is a Greek word for the number ten thousand.  So some people believe that if you just think of replacing myriad with 10,000 you can tell if the usage is correct.  Following that logic, it doesn't make sense to say "there are a ten thousand of okapis living on Mars".  However apparently the use of myriad as a noun in English dates back to the 16th century; before it was used as an adjective.

So everyone can rest easy now.  We're both right.