Graphical information, such as a structural chemical formulae, composed of nodes and links between the nodes, or in a chemical formula ring positions and bonds, are coded by means of logic circuits responsive to actuation of a keyboard. The graphical data coded in binary digit form are stored, while contents of the store are scanned, decoded and applied in analog form to a display device. When recorded on a suitable medium they are made machine readable, for searching or similar processing. A luminous cursor indicates on the display the part of a structural formula that is subject to the next keyboard action. The store is organized about fixed display locations available as nodes. Alphanumeric characters identify atoms at nodes. Single, double or triple bonds in any of eight directions from a node towards another node may be registered and displayed. A cursor address register, a store address register and a comparator are used. Registering at one node a bond designated by character and direction transfers the cursor to the node at the other end of the designated bond. Other transfers of the cursor may be effected by the space bar with the use of the appropriate directional keyed instruction.