SQL buffer stores the most recently used SQL commands and PL/SQL blocks. It does not store the SQL* Plus commands. The SQL buffer can be edited or saved to a file. A SQL command or a PL/SQL block can be executed by entering a semicolon (;) or a slash (/), or by using the RUN command at the command prompt. When a semicolon (;) is entered at the end of a command, the command is completed and executed. When a slash (/) is entered on a new line, the command in the buffer is executed. It can also be used to execute a PL/SQL block. The RUN command is used to execute a command in the buffer. A SQL command can be saved in the buffer by entering a blank line. Reference: Oracle8i Online Documentation, Contents: "SQL*PLUS Users Guide and Reference", "Learning SQL*PLUS Basics, 3 of 4"