CFDs are a leverage product and can involve a significant risk of loss. Trading CFDs may not be suitable for all, therefore you should ensure that you understand the risks involved and take into account your individual circumstances.
Trader's Glossary

What is Support Level?

When charting an asset’s price action, support is a price level which the market seems reluctant or unwilling to fall below. In other words it is a level at which buying is likely to occur. Traders often use recent lows to plot support lines on the charts they are monitoring because they can be good indicators of an imminent trend reversal. The more times an asset’s price fails to drop below a support level the more that support level is reinforced.