Across the sector buying triggered by host of positive factors helped the benchmark Sensex to regain 18K-mark.

Most of the indices including consumer durable, IT, small-cap, mid-cap, Realty and Bank ended in green on renewed demand from investors and operators.

Sustained buying by Foreign Institutional Investors (FIIs), the main market mover, was the major factor for the Sensex despite continued selling by domestic funds.

Foreign Institutional Investors bought shares worth Rs 2,097.26 crore in the first four trading days of the the current month.

The revival of monsoon rains too further boosted the market sentiment as good rainfall would boost farm output and rural income, and lower food inflation.

Auto stocks firmed up after strong July sales reported by some auto companies. Banking segment continued to attract good buying support.

IT counters were in demand after the Nasdaq-listed firm Cognizant Technology Solutions announced stellar Q2 results, beating its larger peers by a huge margin and also revised its 2010 guidance significantly