The Ncurses package contains the ncurses, panel, menu and form libraries. It also contains the clear, infocmp, tic, toe, tput and tset programs.
The libraries that make up the Ncurses library are used to display text (often in a fancy way) on the screen. An example where ncurses is used is in the kernel's "make menuconfig" process. The libraries contain routines to create panels, menu's, form and general text display routines.
The clear program clears the screen if this is possible. It looks in the environment for the terminal type and then in the terminfo database to figure out how to clear the screen.
The infocmp program can be used to compare a binary terminfo entry with other terminfo entries, rewrite a terminfo description to take advantage of the use= terminfo field, or print out a terminfo description from the binary file (term) in a variety of formats (the opposite of what tic does).
Tic is the terminfo entry-description compiler. The program translates a terminfo file from source format into the binary format for use with the ncurses library routines. Terminfo files contain information about the capabilities of a terminal.
The toe program lists all available terminal types by primary name with descriptions.
The tput program uses the terminfo database to make the values of terminal-dependent capabilities and information available to the shell, to initialize or reset the terminal, or return the long name of the requested terminal type.
The Tset program initializes terminals so they can be used, but it's not widely used anymore. It's provided for 4.4BSD compatibility.