Looking at the linotype keyboard, and the silvery metal lines that are produced by the linotype machine, it is clear that linotype is a vast improvement over the composing stick and cases of type used for hand-set type. With individual keys for each letter that you type on by pressing down on the keys, it looks like it could have been part of an early computer. However, it is far from being the revolutionary technology that we might mistake it to be. Linotype made it possible to set lines much faster than by hand, but the underlying technology essentially mimicked the process of hand setting type rather than introducing a novel method of typesetting.
Pressing the linotype keys allows the linotype machine to select the correct matrices for the letters that were typed and hold them into position. The linotype keyboard has 90 keys, different individual keys for lower case, upper case, and punctuation. This step is analogous to the hand selection of type from the tray and keeping it in place on a composing stick. While the linotype makes this process much faster, it is essentially just helping select the correct letters and putting them in order.
The next step is the casting of the matrices into slugs that represent a line of type from the previously selected matrices. The entire line is cast as one entire metal unit that is ready to be used for printing on the press. This step is analogous to removing the type from the composing stick, and keeping it in the lines in which they were set, making it ready for use on the press.
Finally, the matrices that were used to cast the line are returned to the proper location in the linotype machine, to be selected by the keyboard again later. This step is analogous to returning the type to the tray after the type has been used. An advantage with the linotype machine is that the matrices can be reused even before the line has been printed, as the slug has already been cast, whereas the hand-set type cannot be reused until the page has been printed, meaning that the number of matrices needed for the linotype machine can be far fewer than the type needed in a type case.
In summary, the linotype machine certainly was much more efficient than hand-set type, and made it much easier to create type to be printed on a printing press; however, the technology was not a significant departure from hand-set type. While linotype was a useful invention, it was fundamentally simply a mechanization of the entire process of hand-set type.