A shorter version -

A thumb drive is a storage device, it holds files just as your PC does. Use it to backup files (duplicate copies) or to move them to other PCs. The socket it plugs into is called a USB socket. USB is a utility connection, used to connect dozens of other things to a PC like mice, keyboards, other external memory, smartphones (to take off photos or add music), tablets, etc etc.

With thumb drives (as when I'm buying wine, coincidentally), I always shoot for the middle of the available price range. I don't want the cheapest and I don't need the most expensive. The size you need depends upon how much you want to put on it. A 64 GB (gigabyte) thumb drive isn't needed if you have 5 GBs of data to store on it.

Is it secure? It depends on where you physically keep it. Can you use a password? Yes, many offer that, but I always advise people to NEVER use file passwords. I've seen more harm than good come from it. If you're worried about security, put it into a safe deposit box. Otherwise, it has the same stuff on it that your PC has and if you don't worry about that, you shouldn't worry about your thumb drive(s).

Good idea, Snidely, regarding the cons of having it password-protected.

I've heard/read that you shouldn't use them as storage devices, they're just to transfer info. Is there any reason they can't be be loaded full of files as a back-up and left for when you need it?

Thumb drives, while not as failure prone as they used to be, aren't up to a lot of read/write, from what I've read. If you mean write a number of files and put in a secure place for storage, they're probably fine. Not so much for things like daily backups.

The other things about them is that they're very easily lost, heated, wetted, bitten (think dog), and otherwise abused or destroyed. Because it fits on a keychain, people think it's as sturdy as a brass keyfob, but it just isn't. A big use for them is for students carrying their files back and forth between computers at home and on campus, where the files would be recorded in their accounts should a water balloon fight go wrong for the drive. Less secure, is when they're used with public access computers, like at a cafe or library, where the user doesn't save to the cloud as well (better to have a separate cloud account with a different password for documents you're saving in public rather than not saving). It's not so much the drives that are insecure as the "sneaker-net".

Most of ours were FREE after rebate. They offer them around X-mas every year. We wear them around our necks on a fabric necklace when on vacation. People we're traveling with want pictures of themselves or of the dives we're all experiencing....so we make copies of our pics and hand over the "thumb drives"....not really caring if we get them back....but we always do. :0)

We've never paid any attention to brand. The size is what we look at and pay accordingly.

I agree with pillog.

They don't last forever, not a good choice for one's only means of long term storage. Yes, they have a limited read/write cycle useful life, but it's something more than 50,000 cycles, more than most people would ever encounter. For small amounts of important things for long term storage, duplicate your data on other computers also or use a mechanical USB drive AND also something online. For large amounts of storage, I recommend simply multiple external hard drives. Remember to power them up occasionally.

I have a SD card permanently in one of my PCs, to use reduce wear and tear on my hard drive for a particular app's repetitive read/write operations (an SD card has the same innards and characteristics as a thumb drive) This app produces a large volume of info that comes and goes, multiple gigabytes per week. At that level of abuse, I've replaced the SD card once, after about 5 years. They're ready for a lot of use.

I've used thumb/flash/jump drives for years. I've also washed and dried many with no ill effects, and all files were still there, and the device functioned perfectly each time. :)

Cappuccino is much worse. All that sugar and milk. :)

One caution: Flash drives contain a "keep alive" battery. That battery may be good for 10 yrs or more, but it is one of the weak points. Beware that sometimes a store may have on sale older drives they wish to move off the shelf. Before you purchase a 'bargain' drive check its date of manufacture on the packaging. If the drive is 5 years old, it is better to buy a newer unit.

The memory junctions do wear out. Those are good for about 10,000 writes and rewrites. That's old information so I expect there has been improvements, however, those will eventually wear out. Manufacturers have done a clever thing. internally, these drives contain a program that control writing process. To improve the life of the unit, the internal control shifts the partition and moves the write location so that with use the entire drive gets used, not just the front end. Most of the time, a drive has more space than what is stored on it, so shifting the data location extends life of the junctions by shifting the data location.

These drives are just fine for data storage and composing letters with a word processor, or storing photos. I do not recommend using them for active gaming where thousands of rewrites occur during a game session. Its ok for storing the game's data file, but for playing, copy the data files to the hard drive and when the game is done, copy the new data files back to the flash dive.

Nope, there's no battery in a so-called flash or thumb drive. They're made using non-volatile semiconductor memory and powered only by the USB connection (when plugged in to one).

OK, so a flash drive looks like it's not the best back-up option for me to save family photos (the main options being a photo-hosting site in the cloud, burning them to a DVD or using a small portable external hard drive; I actually have used one that I've used to back up my laptop).

I think the external hard drive -- once I choose a photo-hosting web site (and I know that some people use multiple web sites for that to improve their odds against companies going out of business, database malfunctions, etc.) -- is probably a slightly better bet. Am I wrong?

Technology changes so quickly that it's hard to figure out which path to take sometimes!

pammyfay, remember that to be certain, one needs at least two copies of important files.

You say your new PC doesn't have a hard drive. If there's enough room so that you can keep one copy of all files in their "cloud", then your second copy can be on a hard drive or thumb drive. If the cloud capacity you have access to is limited and inadequate, then use two external devices. One can be a thumb drive. The reason to have two copies is that with two, the likelihood of both failing (and you losing your data) is very, very low.

You'd probably do well to use a photo hosting site for sharing your pictures and accessing them for yourself, a portable hard drive backup for storing them locally, where you can have physical hands on them, and a couple of thumb drives you can keep elsewhere. A safe deposit box. Your parents' or kids' house, or somewhere equally trusted. Have a large tie envelope or shoebox with an elastic to keep it closed, that has your name all over it, so there won't be any question of whose it is or why it's there, and put your thumb drive in that. That should also protect it from cappucccino and dog mauling. Every time you come to visit, bring an updated version with your new pictures, and swap it for the one that's there. Do the same thing with all your data backups.

SnidelyWhiplash:
I did some research and found that you are correct. Thumb drives contain NAND memory of the type (non-volatile) that does not require a voltage to retain its state. Those do have a limited life of rewrite cycles. Kingston is up to 100,000 cycles and is working to extend the average life to 1,000,000 cycles. Average life is the point where half of the population has failed.

Snidely and plllog: Thanks for confirming what I thought I should do.
(Next question for everyone: How do you remove a "like" that you mistakenly put on your own post?? No, just kidding -- I can live with it there!)