What’s the difference between those basic modules :
Documentation says all do the same (Writes a text string to the output page).
In order to have the best performance , what module shall i call ?
I need to optimize ALL in my system(NATWEB appl. ADA DB, Web server, etc) because the number of users is increasing very quickly.

Thanks in advance.

The major difference is the handling of trailing white spaces, and additional line break.
:arrow: W3TEXT will examine the given string for trailing white spaces and deletes them.
:arrow: W3TEXTLINE will do the same as W3TEXT but will add a line break at the end. This is useful for pretty printing, but most times not necessary.
:roll: W3TEXTDYNAMIC takes the given string as it is; this is the fastest way!
:arrow: W3TEXTLINEDYNAMIC will do the same as W3TEXTDYNAMIC but will add a line break at the end.
:arrow: W3TEXTARRY will compress the given (A1) array with a given length back into a string. This call is only for historical reasons.

Thanks Eric for this useful info.