Lead-in/lead-out

ive done a search, but i cant seem to find out what exactly lead-in/lead-out is :confused:. if any1 is able to elaborate on this, it would be greatly appreciated. Thanks in advance. :slight_smile:

@ mk_In
Here’s what i found on your query … cdr
LEAD IN The first part of a CD-R recording session, which starts 25 mm from the dead center of the disc and takes up 4,500 sectors. The table of contents is written into the lead-in when the session is closed. Its purpose is to allow the drive to synchronize and to hold the table of contents. If the disc is not closed, it contains the address of the next session.
The lead-in area of a compact disc session is the starting part of the disc. It contains the table of content for the session, and the address of the next available free part of the disc available for the start of the next session, unless the disc is closed and therefore no more sessions can be added, or the disc is not multisession.

LEAD OUT … A group of sectors written at the end of a CD-R recording session that indicates the end of the data. The lead-out is always toward the outer edge of the disc. The first lead-out is 6,750 sectors, and all subsequent ones are 2,250 sectors.
The lead-out area is the ending part of the compact disc session. When the session is closed, the lead-out area is written.

The first lead-out is 6750 sectors (about 13 megabytes) long, each subsequent lead-out is 2250 sectors (4 megabytes) long.

Source of info Wikipedia

ah…thanks :), i assume lead-in/lead-out is also the same for dvds then rite? thanks again for your response. :slight_smile: