Online reviews are a good example of the positive and the negative of the internet. They can be a great way to help decide which products and services to buy. They can be a great way to help others make these decisions. And they can be a fount of lies.

Because the internet makes it easy to fake who you are, many user reviews are faked. Still, 78 percent of people believe online reviews are reliable, according to a recent survey by ReportLinker.

Not surprisingly, ReportLinker also found the most popular category of online reviews is electronics, with 71 percent of those surveyed mentioned they use the internet for this. Hotel and restaurant reviews are the next most popular type of review searches, mentioned respectively by 53 percent and 52 percent of people. They're followed by cars, entertainment, clothing and personal care products.

For general product reviews, the two most popular sites are Amazon and eBay, with each mentioned by 57 percent of people. For restaurant reviews, Yelp is the most popular site/service, mentioned by 53 percent of people.

It's also not surprising that people are more likely to read reviews than write them, with 51 percent of people saying they take the time for this.

Some individuals and companies hire themselves out to write fake reviews, positive and negative. Fortunately, large sites such as Amazon, Yelp and Angie's List do a good job of weeding out the most blatant of these planted reviews and of making the reviews that can be trusted more prominent on the website. These are the same reviews that others find most useful.

Fake reviews, however, do make it through, particularly on smaller sites. But there are steps you can take to diminish the chances of being taken in by them.

Discount reviews that are gushingly positive. Be wary also of stellar reviews that include only a minor negative. These could be legit, or they could be planted by a clever paid reviewer. Likewise, Ignore reviews that are scathingly negative.

Lean toward products or services that have received a lot of reviews, and be more careful if you find only one or two reviews.

Discount reviews that describe the reviewer in too much detail. This could be a tip-off that a public relations firm is trying to target the demographic group represented by the reviewer's self-description.

Discount reviews that are merely a list of features. The best reviews, whether written by an ordinary user or a professional, indicate the benefits you can derive from using the product or service. Consider those core features you'll actually use rather than fancy features you probably won't.

Pay more attention to reviews that compare the product or service to similar ones. The best reviews put a product or service into context rather than just talking about it as if in a vacuum. Comparative reviews also indicate that the reviewer likely has more experience with the area and can be more relied upon.

Don't be swayed by reviews that include a lot of impressive-sounding jargon. This may indicate the reviewer is just trying to impress others, though depending on the product or service, some jargon may be necessary for a full evaluation.

Look for commonalities. If a number of reviewers offer the same opinion about a quality of a particular product or service, this gives the opinion more validity.

Ignore reviews that sound too much like other reviews of the same product or service. This could indicate that they were written by the same person.

If you write reviews, put yourself in your readers' shoes. Write for them, not for yourself, to help them make buying decisions.

Depending on the product or service, some readers will be newcomers, some will have a bit of experience with the category, and some will be experts with lots of technical knowledge.

Ask yourself what the product or service promises, then spell out your opinion about how well it achieves those goals and whether it's a good value. Specify why you feel the way you do.

Also talk about anything the product or service doesn't do, or any features it may lack that you would have found useful.

Reviews are almost always better when you've worked with a product or service over a period of time rather than merely providing a "first look."

The best professional reviewers distinguish themselves by talking about similar products or services on the market. Amateur reviewers won't always be able to do this, but if you have this background, it will make your review more useful.