I first started editing fonts in the late 1980’s using CorelDraw 4.0, which had an export filter for TrueType fonts. This was back in the days of Windows 3.1 and ANSI character sets. Standard fonts did not include the characters with diacritics (accents) that I needed, so I had to edit my own fonts. It was a slow process, because the export filter crashed very often.
In 2002 I got a copy of FontCreator 4.0 and the task became a lot easier. Later, I got involved with coding the data used by FontCreator for positioning diacritics in composite glyphs (like ā, é, ì, õ, ü), which are needed frequently for non-English languages, especially Pali and Vietnamese.
The software has come a very long way in the 16 years since I started using it. Now we can create colour fonts, add and edit OpenType features with a graphical editor, import vector outlines from Adobe Illustrator or SVG images from Inkscape, as well as PDF files. It is a powerful program, with a long learning curve, but I have created many tutorials that you can read or watch.
Font Editing is Harder than One might Think
Those who are new to editing fonts soon discover that there is a lot to learn. It is not just about designing glyphs with appealing shapes, the letter spacing, line spacing, and mapping of glyphs to code-points has to be done right too. There are many built-in tools to automate the process, especially in the Professional Edition, but new users will need to read the help file and ask questions on the support forum.