life cycle – Two words, not lifecycle.
line numbers – Lowercase and use figures when naming word lines in individual lines of a text: line 1, line 2. But: the first line, the 10th line.
lists – Use a colon after introductory text before a bulleted list. Lists should contain parallel structure. Capitalize the first word of the bulleted content, and finish with a period only if it is a complete sentence. See lists section also.
login, logon, logoff, log in – Login, logon and logoff are all nouns. Two words create the verb form.
loan locker, lending locker, loan closet, lending closet – When referring to this program or service in general, lowercase the term. Capitalize the term when referring to a specific program or service on a specific installation. For example: Lending lockers (also known as loan lockers, or lending or loan closets) allow service and family members to borrow basic household goods while they await arrival of their own personal household goods after a PCS. For an example where you would capitalize the term: The Marine Corps Base Quantico Loan Locker allows service members, family members and DOD civilians to borrow basic household items for a period of up to 30 days while they await the arrival of their household goods. Note: The need to refer to installation-specific programs and services most commonly arises on the MilitaryINSTALLATIONS website.
long term, long-term – Hyphenate as a compound modifier: They are focusing on the long term. Her unit has a long-term overseas assignment.