Capitalise the first letter of computer programs and applications (including web applications, add-ins, toolbars and extensions that can be added to applications), and follow manufacturer (or owner, if open source) usage:
ChemDraw LaTeX MULTAN78 InDesign PowerPoint MacOS GFortran
WeChat Facebook Gmail WorkflowMax MathType EndNote X9
Sometimes these names change with time. Mac OS X became OS X and then macOS. In general, choosing the current usage and providing adequate ancillary information (eg version numbers or names), if needed, gives a good balance between consistency of appearance and accuracy.
Capitalise the first letter of programming languages:
Fortran Java Smalltalk Python Rust
Remember that sometimes (eg for compatibility reasons) a version or range of versions must be indicated. Be as specific as necessary:
Fortran 95 Python 3 Python 3.1 Python 3.5.1 Python 3.8.5
Protocols are written in lower case because they are essentially descriptions:
hypertext transfer protocol (HTTP) network news transfer protocol (NNTP)
Names of established standards are rarely written out in full, but should follow the usual rules for capitalisation of international and national standards:
ASCII (American Standard Code for Information Interchange)
UTF‑8 (8‑bit Unicode Transformation Format)
Note that unicode is short for universal coded character set (see Syllabic abbreviations, and is written in lower case unless in a formal title (referring to the Unicode Consortium or similar).
Some terms begin with a lower-case letter or number, and this cannot be changed because it is an important part of the name. Do not use these terms at the start of a sentence – recast the sentence if necessary:
eSATA iPad i686 802.11n
In formal writing, do not use a program or command name as a verb:
Contact the coordinator using Skype not Skype the coordinator
Use ssh to log in to the server not ssh into the server