Whenever a new site is launched, Google tries to figure out what this new site is all about. He scans the content and the internal linkage but he can’t determine the site’s theme and
topic from that alone. On the other hand, Google knows the authorities in each domain, so he will ask them for a helping hand. How? Through inbound links,
links pointing from other sites towards yours. So, before a reasonable amount of quality links from authority pages is not attracted, the site will be sand boxed.

What does sandbox mean?
You can consider Google’s sandbox as an extended probation period for your site. A period given to you to prove you’re worthy. Basically, the sandbox is a penalty or devaluation in the Google SERPs of new sites. Most of the time this devaluation will effect only the competitive keywords targeted, as other long tails searches would do just fine and receive high SERPs positions.
Of course, with proper techniques, there are possibilities to avoid or fast elude Google’s Sandbox, as you will see down below.

How do i know if my site has been sand boxed?
You can always use these kinds of tools: Sandbox check tool.
Or you can go the safer old fashioned way and try some of the following tips:

* are you ranked 1-10 in Yahoo and MSN for a "keywords" search but you’re nowhere in Google?
* are you ranked in among the first results for a 8-10 keywords matching exactly a posts title?
* do you rank well for wider non-competitive terms?
* is your site ranking well for a long tail keyword but is way further in SERPs for the same all keyword?

If the answer to all the questions above is yes, then you are facing a "sandbox" problem. You’ll see further down what you have to do in this case.

Can I avoid the Sandbox?
Definitely. Before placing it in the Sandbox, Google gives every new site the initial SERPs boost. If during this short period you manage to "gain Google’s trust" by providing quality and unique content and acquiring a decent number of natural links from other sites, including authorities, you might just skip the probation period. Of course there’s nothing sure here, cause after all we’re talking about Google… But this site for example has never experienced Sandbox, as one of its first articles gained lots of exposure and natural links.
Of course, the best method for avoiding sandbox is to buy an older site (could be expensive though). This will also bring the "age bonus factor" into equation, proving to be useful later on, as we know how much weight does Google put on age in his ranking algorithm.

My site is in the Sandbox. How can i get out? Help!
First of all, there’s no need to panic. This "sandbox problem" sounds worse then it is. With a little bit of work and a decent amount of patience, most of the sites will get over it. So, let’s see what every site owner should do once he is sure his site is affected by a devaluation:

* don’t panic and don’t use Black or Grey methods. Anything from spamming to buying links (except buying links inside posts, that would appear to be 100% natural, which are recommended) should be out of the question.
* get more trusted links. I would not recommend on site wide links (also there are others claiming otherwise), but links inside the content for old and established sites, preferably authorities from your domain.
* build links slowly (no more than 10 each week)
* build quality and most importantly, unique content. Give each page an unique title and description (Meta tags of course). Also, each post should have 250 characters (that’s just my opinion) of unique content at a minimum.
* don’t get only links pointing towards your home page but also deep links. This helps your site seem less "hollow". After all, if we’re talking about natural links, it’s more then normal that other sites would link to the posts they like rather than your home page, no?

All these methods are just theories gathered from the community. In most cases, sticking to them should get you out of the sandbox, but there’s nothing 100% sure. :)
Anyway, the only real escape from the Sandbox is time. Depending on the competitiveness of your most important keywords, that time can vary from one to six months, with three to four months being the normal duration. In the meantime, continue to improve your site, and be prepared to make a rapid rise once the Sandbox probation ends, cause if you’ve spent the probation period doing the right things, you will…

But i still need traffic!
Most of you won’t settle to working on the site without seeing any traffic during the "sand boxed" months. But don’t worry, there are lots of other ways to get traffic besides Google. After all, it’s not safe for any site to rely on only one source of visitors, especially when that source is as unreliable as Google… Anyway, here are the other traffic sources you should take into consideration:

* Yahoo and MSN. Even though Google is the dominant search engine, Yahoo and MSN together hold a good amount of traffic (around 50% of Google’s share). So, they could be a great alternative to Google. Trying to rank well in Yahoo and MSN might not be that hard, as their algorithms are not as advanced as Google’s is. Generally, any site with decent links and good On page SEO should do OK here.
* link baits, viral promotion and social marketing are great ways of generating exposure. It’s true, the visitors will not be as targeted as the ones coming from search engines, but they compensate by numbers. Knowing how to write a proper link bait post and how to promote it is a must, as these methods could hurry your "sandbox exit", by attracting lots of links from related sites.
* PPC: if you’re looking for targeted visitors and money are not a problem, you could buy some traffic. Google’s Adwords is some of the best way to do it, but Yahoo and MSN provide their own similar services. It’s just up to you