I will explain.

 (1) When arrive writing, from this webpages all over the world, at the server computer in charge, the server will write and display them on the bulletin board. (In index.php, ← PHP start →, ← PHP end →.)(You can read a "index.php" in two down area from here.)

 (2) The server computer will doing display the most recent writing at the top of the bulletin board. (In index.php, ↓1st↑, ↓2nd↑.)

 (3) When the 6th writing comes, the server computer will delete the oldest (bottom) writing. (In index.php, ↓3rd↑.)

 (4) When the writer clicks "submit" without writing, the server computer will temporarily displaying 'Please enter a comment' and no saving. (In index.php, ↓ 1st ↑, from "if(empty", to "return false".)

 (5) When the writer clicks "submit" with more than 100 words, the server computer will temporarily displaying "Please enter within 100 words" and no saving. (In index.php, ↓ 1st ↑, from "if(mb_strlen", to "return false".)

 (6) When the writer finishes writing and clicks “submit”, the server computer will move the screen to near the latest writing. (In index.php, ↓Writting point↑, ↓Let's try it↑.)

  I'm using two texts （"memoone.txt" and "memotwo.txt"） in this bulletin board. The reason for this is that the server computer need have two texts for doing them. Them is that the most recent writing at the top of the bulletin board, and the five writing, but nothing writing a sixth a oldest.

  In "index.php" ↓1th↑, the server computer delete all previous wrote in "memoone.txt", and after writes the latest writing.

  In "index.php" ↓2th↑, the server computer reads all past writing in "memotwo.txt" and after the server writes these to "memoone.txt". In other words, in "memoone.txt", all past writing is written under the latest sentence.

  In "index.php" ↓3th↑, first the server read "memoone.txt", and after adjust Enter etc. with "filesize" and "explode", write 5 writings to "memotwo.txt", and don't write for first writing (oldest).

  If I don't install these programs, the computer won't be able to display the writers' writing separately..

  It's difficult for me to write a manuals for HTML, PHP programs, so I'll try to improve them little by little.