In the last few years, online shopping has developed and matured into a mainstream phenomenon. Many people are saving a lot of money by shopping online, but in order to really maximize your savings you need to learn your way around the internet shopping scene. As with any other kind of shopping, mastering certain nuances can result in big savings online. Fortunately, there are some websites that help you do just that.

Online shoppers may be missing out on big savings if they aren't using coupon codes. Most merchants have a box for entering a coupon code or promo code during the checkout process. These codes are not usually available at the merchant's site. The best way to get hold of these codes is to visit a website dedicated to providing coupons.

One such site is MeanBargains.com. One complaint about coupon sites is that coupons found online are either expired or invalid. Instead of covering a huge list of online merchants, MeanBargains.com concentrates on a smaller list of merchants and strives to keep coupons up to date. It has deals and coupons for most of the big online merchants.

SimplyBestCoupons.com says that with its enormous list of online merchants and coupons, consumers have no need to look elsewhere. Coupons are arranged by a growing list of categories, and even include things like tax preparation services and cell phones. They say that many of their coupons have no expiration date.

You can even use your mobile phone, PDA or other wireless device to search for coupons, without being concerned with formatting issues. Wow-coupons.mobi is a mobile friendly website where you can search for retail, grocery, restaurant, travel and other coupons. You can check for coupons on products you see while shopping, then print those coupons at home or elsewhere and save a lot of money.

Online coupon site CouponShack.com uses a blog to provide consumers with a daily selection of hand-picked deals and discounts. They say they receive about 2,000 emails a day from various vendors, and they use the blog as a way to spotlight the best deals and discounts. They also have some coupons available only at their website.

Joel Comm, owner of Dealofday.com, offers some tips for online shoppers.

- You may be able to apply coupons clipped in the "real world" to online purchases. Office supply stores, for example, sometimes provide coupon codes in printed mailers and newspaper pull-out sections.

- Take advantage of multiple discounts. Shoppers can sometimes take advantage of a "first time buyer" discount in addition to another coupon. Also watch out for freebies given away with a purchase of a given dollar amount.

- Check the reputation of merchants at a site such as Bizrate.com, which provides consumer ratings.