# Invention of matrix symbols

Who first did use the symbol $\begin{bmatrix} 1 & 2 \\ 3 & 4 \end{bmatrix}$ for a matrix and similarly $\begin{pmatrix} 1 & 2 \\ 3 & 4 \end{pmatrix}$?
Why do these two conventions exist independently to the present day?

Were whenever efforts made to unify the symbols?

• – Mauro ALLEGRANZA Jan 31 '18 at 13:50
• @MauroALLEGRANZA Thank you for the link, it gives some insight into problem but it doesn't clarify it in reference to two most used symbols nowadays. – Widawensen Jan 31 '18 at 14:02
• In "A Memoir ..", as I see the symbol is very close however a little different.. entries are additionally separated with commas.. to the second book it seems I have no access.. – Widawensen Jan 31 '18 at 14:26
• @MauroALLEGRANZA I've read the "A memoir ..." in one breath, it is wonderful, delicious.. I'm very grateful for providing this particular link.. Cayley surprisingly was using the symbol which is a mix of two modernly used symbols.. thank you also for telling about Cullis, who did popularize "rounded parenthesis" ? we still don't know , do you know why some people use the first symbol, others the second one ? It depends on country ? why there is no unification ? Maybe some interesting story is behind all of this.. (BTW - you said so much that you could consider also to give it as an answer ) – Widawensen Feb 1 '18 at 13:20