Currently, I am going through the script of The Battle of Algiers. On the left margin, there are numbers starting from 1 to 146. It is a 120 minutes long film. What are the significance of these numbers on the left from 1 to 146?
For this script at least, the numbers correspond to the scenes.
Each number in the left margin appears at the beginning of a new location. At a guess, this could simply be to make writing easier for the screenwriter, or perhaps to correspond to clapperboard information. These possible uses are only guesses, however.
As seen in @Reed's comments, this is by no means an industry standard, but for the purposes of the specific script chosen in the question, the numbers in the left margin are so scene numbers.
Number = Scene
Screenplays are usually formatted in such a way that one page roughly equates to one minute, and, in a shooting script, the scenes are numbered.
Notes on the length of The Battle of Algiers:
According to the French Wikipedia article, there is a French dubbed version of the movie that is 157 minutes long. Finding out when and why the shorter versions of 117 and 121 minutes were created would require more research and probably the ability to read Italian, but it is clear that a version of the movie exists that is about as long (in minutes) as the script (in numbers).
A movie script is not a transcript of a movie. A script is a roadmap for the production of the movie. Directors often deviate from scripts during filming as well as in the cutting room. Disregarding the 157 minute French version, the short version might have simply been the best version for the director when he was on the set and later when he viewed the material he had filmed.
In the case of this specific script, we should hold in mind that we are not seeing the original (Italian) movie script, but a translation of it, and that we do not know if the numbers were part of the original and what kind of script it was (shooting script, spec script, etc.).
Looking at this script, it becomes obvious that the numbers correspond to the scenes, but we do not know if the numbers were in the original script or have been introduced for the online presentation only. We can therefore draw no definite general conclusions from this online presentation of a translated script as to what numbers might mean in other, real scripts.
Normally they are minutes
roughly 1 page equals about 1 minute of visual time.
But it is not an exact science and here 146 pages translate to 120 minutes..
most likely this is caused by long descriptions which only take a short time time to show rather than tell.
that 1 page= 1 minute is truest for talking and some action scenes, still as they are not the same media there can be no certitudes in transforming the writen word into images.
"Could you provide a reference for your claim that "normally they are minutes"? All references I have found say that in a script the scenes are numbered: google.com/search?q=script+numbering – what 3 hours ago"
It is a rule of thumbs used in the movie industry; I know because it is what any inspiring screenwriter aims for. The length “standard” is a 130 page script for a 120 movie time minus 30 minutes edited out for a net result of a 90 min movie. I know because I lived in Hollywood, tried my hand at screen-writing, and had friends in the industry but I am pretty sure it is in most screenwriting manuals here is a reference:
"The common rule that many spit out is: "One page of film script equals one minute of screen time."" http://www.scriptwritingsecrets.com/Size_Matters.htm
"It’s true that a lot of movies clock in at 100 minutes or less, and that the one-minute-per-page rule of thumb really depends on whose thumbs are doing the measuring." http://johnaugust.com/2003/script-length
If your demand for clarifications was about the numbering, a "Shooting" script is not a regular script; it has been modified by the director for convenience
"Shooting scripts are distinct from spec scripts in that they make use of scene numbers (along with certain other formatting conventions described below), and they follow a well defined set of procedures specifying how script revisions should be implemented and circulated." http://en.wikipedia.org/wiki/Shooting_script
Edited from COMMENTS, someone can find this helpfull in the future...
”confusing that each scene corresponds to a number” […] you mean that an answer regarding this specific script by no means is applicable to any other?"
That’s probably a shooting script, also remember that there are no real standards, there are preferred versions only, it is a loose industry and I have seen very big exceptions to some commonly held rules. Basically, if you are good, you can do what you want, they will buy it and a hired screenwriter will polish it, also some directors have individual preferences and their scripts may reflect that. What you have to remember is that a script is not a final version, it is only an intermediary step to a final product, so pretty much anything goes.
while they are common rules, or rules of thumb, there is no law, and while there can be exceptions a regular script is about 1m=1p, after it is bought it can be transformed in various ways, the scene numbers in working scripts are because scenes are shot out of order in filming. Yes both you and What were right about shooting scripts, but the published version of a script is more often the speculative script and sometimes the post-movie script. Also what I know is movies; things may be different in other Medias