What do you mean by stamp under The Indian Stamp Act, 1899? Which instruments are stamped with adhesive stamps ?

According to section 2(26) of the Indian Stamp Act, 1899, "Stamp" means any mark, seal or endorsement by any agency or person duly authorized by the State Government and includes an adhesive or impressed stamp for the purposes of duty chargeable under this Act. Section 11 deals with the use of adhesive stamps. This Section provides that the following instruments may be stamped with adhesive stamps, namely: Instrument chargeable with a duty not exceeding 10 naya paisa except parts of bills of exchange payable otherwise than on demand and drawn in sets; Bills of exchange and promissory notes drawn or made out of India; Entry as an advocate, vakil or attorney on the roll of a High Court; Notarial acts; Transfers by endorsement of shares in any incorporated company or other body corporate. The use of the words 'may be stamped' really connotes 'shall be stamped'. The rules framed under the Stamp Act as well as under the relevant state laws invariably provide that the adhesive stamps shall carry special words, to indicate the use to which the stamps can be put.